diff mbox

[V5,1/3] pci: Add PCIe driver for Samsung Exynos

Message ID 000b01ce6839$0f0455d0$2d0d0170$@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jingoo Han June 13, 2013, 1:22 p.m. UTC
Exynos5440 has a PCIe controller which can be used as Root Complex.
This driver supports a PCIe controller as Root Complex mode.

Signed-off-by: Surendranath Gurivireddy Balla <suren.reddy@samsung.com>
Signed-off-by: Siva Reddy Kallam <siva.kallam@samsung.com>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
---
Tested on Exynos5440.

 .../devicetree/bindings/pci/exynos-pcie.txt        |   71 ++
 drivers/pci/host/Kconfig                           |    5 +
 drivers/pci/host/Makefile                          |    1 +
 drivers/pci/host/pci-exynos.c                      | 1078 ++++++++++++++++++++
 4 files changed, 1155 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/exynos-pcie.txt
 create mode 100644 drivers/pci/host/pci-exynos.c

Comments

Arnd Bergmann June 13, 2013, 2:13 p.m. UTC | #1
On Thursday 13 June 2013 22:22:31 Jingoo Han wrote:

> +struct pcie_port_info {
> +	u32		cfg0_size;
> +	u32		cfg1_size;
> +	u32		io_size;
> +	u32		mem_size;
> +	phys_addr_t	io_bus_addr;
> +	phys_addr_t	mem_bus_addr;
> +};
> +
> +struct pcie_port {
> +	struct device		*dev;
> +	u8			controller;
> +	u8			root_bus_nr;
> +	void __iomem		*dbi_base;
> +	void __iomem		*elbi_base;
> +	void __iomem		*phy_base;
> +	void __iomem		*purple_base;
> +	phys_addr_t		cfg0_base;
> +	void __iomem		*va_cfg0_base;
> +	phys_addr_t		cfg1_base;
> +	void __iomem		*va_cfg1_base;
> +	phys_addr_t		io_base;
> +	phys_addr_t		mem_base;
> +	spinlock_t		conf_lock;
> +	struct resource		cfg;
> +	struct resource		io;
> +	struct resource		mem;
> +	struct pcie_port_info	config;
> +	struct clk		*clk;
> +	struct clk		*bus_clk;
> +	int			irq;
> +	int			reset_gpio;
> +};

You mentioned that you'd use u64 for the resources here but did not.

> +
> +static void exynos_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32 busdev)
> +{
> +	u32 val;
> +	void __iomem *dbi_base = pp->dbi_base;
> +
> +	/* Program viewport 0 : OUTBOUND : CFG0 */
> +	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> +	writel_rc(pp, (u64)pp->cfg0_base, dbi_base + PCIE_ATU_LOWER_BASE);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> +	writel_rc(pp, (u64)pp->cfg0_base + pp->config.cfg0_size - 1,
> +			dbi_base + PCIE_ATU_LIMIT);
> +	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> +	writel_rc(pp, PCIE_ATU_TYPE_CFG0, dbi_base + PCIE_ATU_CR1);
> +	val = PCIE_ATU_ENABLE;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> +}
> +
> +static void exynos_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
> +{
> +	u32 val;
> +	void __iomem *dbi_base = pp->dbi_base;
> +
> +	/* Program viewport 1 : OUTBOUND : CFG1 */
> +	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> +	writel_rc(pp, PCIE_ATU_TYPE_CFG1, dbi_base + PCIE_ATU_CR1);
> +	val = PCIE_ATU_ENABLE;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> +	writel_rc(pp, (u64)pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> +	writel_rc(pp, (u64)pp->cfg1_base + pp->config.cfg1_size - 1,
> +			dbi_base + PCIE_ATU_LIMIT);
> +	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> +}

And you still don't set up the UPPER halves, which was really the point
of my comment. Same thing for all the other ones.

> +static void exynos_pcie_prog_viewport_mem_inbound(struct pcie_port *pp)
> +{
> +	u32 val;
> +	void __iomem *dbi_base = pp->dbi_base;
> +
> +	/* Program viewport 0 : INBOUND : MEM */
> +	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX0;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> +	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
> +	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> +	writel_rc(pp, (u64)pp->config.mem_bus_addr,
> +			dbi_base + PCIE_ATU_LOWER_BASE);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> +	writel_rc(pp, (u64)pp->config.mem_bus_addr + pp->config.mem_size - 1,
> +			dbi_base + PCIE_ATU_LIMIT);
> +	writel_rc(pp, (u64)pp->mem_base, dbi_base + PCIE_ATU_LOWER_TARGET);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> +}

This makes even less sense than before, it seems like now you only
allow DMA between PCI devices but not to main memory.

> +static void exynos_pcie_prog_viewport_io_inbound(struct pcie_port *pp)
> +{
> +	u32 val;
> +	void __iomem *dbi_base = pp->dbi_base;
> +
> +	/* Program viewport 1 : INBOUND : IO */
> +	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX1;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> +	writel_rc(pp, PCIE_ATU_TYPE_IO, dbi_base + PCIE_ATU_CR1);
> +	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
> +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> +	writel_rc(pp, (u64)pp->config.io_bus_addr,
> +			dbi_base + PCIE_ATU_LOWER_BASE);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> +	writel_rc(pp, (u64)pp->config.io_bus_addr + pp->config.io_size - 1,
> +			dbi_base + PCIE_ATU_LIMIT);
> +	writel_rc(pp, (u64)pp->io_base, dbi_base + PCIE_ATU_LOWER_TARGET);
> +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> +}

Can you please explain what the inbound window is as I asked you?
I still don't see why you would need to set it up like this.

> +static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
> +{
> +	struct pcie_port *pp;
> +
> +	pp = sys_to_pcie(sys);
> +
> +	if (!pp)
> +		return 0;
> +
> +	pci_add_resource(&sys->resources, &pp->io);
> +	pci_add_resource(&sys->resources, &pp->mem);

Now you are missing the offsets. You have to at least pass an offset for one
of the I/O spaces, since they are using the same bus address. The offset must
match the value you pass to pci_ioremap_io.

For the memory space, you should pass the difference between the physical
base address and the bus address. That address happens to be zero with
you DT setup, but I would advise to also try out some other values in DT,
just to ensure it still works.

> +	pp->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);

Ok.

> +
> +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> +{
> +	struct pcie_port *pp = platform_get_drvdata(pdev);
> +
> +	clk_disable_unprepare(pp->bus_clk);
> +	clk_disable_unprepare(pp->clk);
> +
> +	return 0;
> +}

You also don't remove the PCI devices here, as mentioned in an earlier
review.

	Arnd
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Jingoo Han June 14, 2013, 8:18 a.m. UTC | #2
On Thursday, June 13, 2013 11:14 PM, Arnd Bergmann wrote:
> On Thursday 13 June 2013 22:22:31 Jingoo Han wrote:
> 
> > +struct pcie_port_info {
> > +	u32		cfg0_size;
> > +	u32		cfg1_size;
> > +	u32		io_size;
> > +	u32		mem_size;
> > +	phys_addr_t	io_bus_addr;
> > +	phys_addr_t	mem_bus_addr;
> > +};
> > +
> > +struct pcie_port {
> > +	struct device		*dev;
> > +	u8			controller;
> > +	u8			root_bus_nr;
> > +	void __iomem		*dbi_base;
> > +	void __iomem		*elbi_base;
> > +	void __iomem		*phy_base;
> > +	void __iomem		*purple_base;
> > +	phys_addr_t		cfg0_base;
> > +	void __iomem		*va_cfg0_base;
> > +	phys_addr_t		cfg1_base;
> > +	void __iomem		*va_cfg1_base;
> > +	phys_addr_t		io_base;
> > +	phys_addr_t		mem_base;
> > +	spinlock_t		conf_lock;
> > +	struct resource		cfg;
> > +	struct resource		io;
> > +	struct resource		mem;
> > +	struct pcie_port_info	config;
> > +	struct clk		*clk;
> > +	struct clk		*bus_clk;
> > +	int			irq;
> > +	int			reset_gpio;
> > +};
> 
> You mentioned that you'd use u64 for the resources here but did not.

Do you mean the following?

+	u64		cfg0_base;
+	u64		cfg1_base;
+	u64		io_base;
+	u64		mem_base;


> 
> > +
> > +static void exynos_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32 busdev)
> > +{
> > +	u32 val;
> > +	void __iomem *dbi_base = pp->dbi_base;
> > +
> > +	/* Program viewport 0 : OUTBOUND : CFG0 */
> > +	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > +	writel_rc(pp, (u64)pp->cfg0_base, dbi_base + PCIE_ATU_LOWER_BASE);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > +	writel_rc(pp, (u64)pp->cfg0_base + pp->config.cfg0_size - 1,
> > +			dbi_base + PCIE_ATU_LIMIT);
> > +	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > +	writel_rc(pp, PCIE_ATU_TYPE_CFG0, dbi_base + PCIE_ATU_CR1);
> > +	val = PCIE_ATU_ENABLE;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > +}
> > +
> > +static void exynos_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
> > +{
> > +	u32 val;
> > +	void __iomem *dbi_base = pp->dbi_base;
> > +
> > +	/* Program viewport 1 : OUTBOUND : CFG1 */
> > +	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > +	writel_rc(pp, PCIE_ATU_TYPE_CFG1, dbi_base + PCIE_ATU_CR1);
> > +	val = PCIE_ATU_ENABLE;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > +	writel_rc(pp, (u64)pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > +	writel_rc(pp, (u64)pp->cfg1_base + pp->config.cfg1_size - 1,
> > +			dbi_base + PCIE_ATU_LIMIT);
> > +	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > +}
> 
> And you still don't set up the UPPER halves, which was really the point
> of my comment. Same thing for all the other ones.

Do you mean the following?

+	writel_rc(pp, pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, (pp->cfg1_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);


> 
> > +static void exynos_pcie_prog_viewport_mem_inbound(struct pcie_port *pp)
> > +{
> > +	u32 val;
> > +	void __iomem *dbi_base = pp->dbi_base;
> > +
> > +	/* Program viewport 0 : INBOUND : MEM */
> > +	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX0;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > +	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
> > +	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > +	writel_rc(pp, (u64)pp->config.mem_bus_addr,
> > +			dbi_base + PCIE_ATU_LOWER_BASE);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > +	writel_rc(pp, (u64)pp->config.mem_bus_addr + pp->config.mem_size - 1,
> > +			dbi_base + PCIE_ATU_LIMIT);
> > +	writel_rc(pp, (u64)pp->mem_base, dbi_base + PCIE_ATU_LOWER_TARGET);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > +}
> 
> This makes even less sense than before, it seems like now you only
> allow DMA between PCI devices but not to main memory.

Sorry, I cannot understand it.
Could you give me more details?
Also, pseudo-code will be very helpful.


> 
> > +static void exynos_pcie_prog_viewport_io_inbound(struct pcie_port *pp)
> > +{
> > +	u32 val;
> > +	void __iomem *dbi_base = pp->dbi_base;
> > +
> > +	/* Program viewport 1 : INBOUND : IO */
> > +	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX1;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > +	writel_rc(pp, PCIE_ATU_TYPE_IO, dbi_base + PCIE_ATU_CR1);
> > +	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
> > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > +	writel_rc(pp, (u64)pp->config.io_bus_addr,
> > +			dbi_base + PCIE_ATU_LOWER_BASE);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > +	writel_rc(pp, (u64)pp->config.io_bus_addr + pp->config.io_size - 1,
> > +			dbi_base + PCIE_ATU_LIMIT);
> > +	writel_rc(pp, (u64)pp->io_base, dbi_base + PCIE_ATU_LOWER_TARGET);
> > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > +}
> 
> Can you please explain what the inbound window is as I asked you?
> I still don't see why you would need to set it up like this.

Sorry, I was guided to use this inbound from hardware engineer.
without this inbound, Exynos5440 PCIe cannot work at booting.


Surendranath Gurivireddy Balla, Siva Reddy,
Would you explain what the inbound window is?


> 
> > +static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
> > +{
> > +	struct pcie_port *pp;
> > +
> > +	pp = sys_to_pcie(sys);
> > +
> > +	if (!pp)
> > +		return 0;
> > +
> > +	pci_add_resource(&sys->resources, &pp->io);
> > +	pci_add_resource(&sys->resources, &pp->mem);
> 
> Now you are missing the offsets. You have to at least pass an offset for one
> of the I/O spaces, since they are using the same bus address. The offset must
> match the value you pass to pci_ioremap_io.
> 
> For the memory space, you should pass the difference between the physical
> base address and the bus address. That address happens to be zero with
> you DT setup, but I would advise to also try out some other values in DT,
> just to ensure it still works.

Um, I cannot understand it, too.
Could you give me Psuedo-code?
Or, let me know which pcie driver can be the good reference.


> 
> > +	pp->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
> 
> Ok.
> 
> > +
> > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > +{
> > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > +
> > +	clk_disable_unprepare(pp->bus_clk);
> > +	clk_disable_unprepare(pp->clk);
> > +
> > +	return 0;
> > +}
> 
> You also don't remove the PCI devices here, as mentioned in an earlier
> review.

I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
I cannot know what you mean.

Could let me know which additional functions are needed?



> 
> 	Arnd

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Thierry Reding June 14, 2013, 10:53 a.m. UTC | #3
On Fri, Jun 14, 2013 at 05:18:46PM +0900, Jingoo Han wrote:
> On Thursday, June 13, 2013 11:14 PM, Arnd Bergmann wrote:
> > On Thursday 13 June 2013 22:22:31 Jingoo Han wrote:
[...]
> > > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > > +{
> > > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > > +
> > > +	clk_disable_unprepare(pp->bus_clk);
> > > +	clk_disable_unprepare(pp->clk);
> > > +
> > > +	return 0;
> > > +}
> > 
> > You also don't remove the PCI devices here, as mentioned in an earlier
> > review.
> 
> I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
> I cannot know what you mean.
> 
> Could let me know which additional functions are needed?

We don't currently do that on Tegra either. pci-mvebu doesn't do that
either, but they don't implement the driver's .remove() in the first
place.

I think the biggest missing piece is pci_common_exit(), the counterpart
of pci_common_init(), to cleanup a host bridge on ARM. I haven't looked
in detail at the other architectures, but I suspect there must be some
code to call when a host bridge is removed.

Looking at drivers/pci/remove.c, it seems like pci_remove_root_bus()
might be what we're looking at. It isn't exported so it can't be used by
modules, but that can be changed. Is that how a host bridge is typically
removed from the system?

Thierry
Arnd Bergmann June 14, 2013, 12:38 p.m. UTC | #4
On Friday 14 June 2013 12:53:11 Thierry Reding wrote:
> 
> I think the biggest missing piece is pci_common_exit(), the counterpart
> of pci_common_init(), to cleanup a host bridge on ARM. I haven't looked
> in detail at the other architectures, but I suspect there must be some
> code to call when a host bridge is removed.
> 
> Looking at drivers/pci/remove.c, it seems like pci_remove_root_bus()
> might be what we're looking at. It isn't exported so it can't be used by
> modules, but that can be changed. Is that how a host bridge is typically
> removed from the system?

It's fairly new to have host bridges in loadable modules, so I'm pretty
sure it's not supported by the core yet, but it also doesn't seem hard
to do. I think you are right with regard to pci_remove_root_bus,
and Bjorn might be able to provide more information.

Ideally we should be able to load and unload the pci host driver
in a loop indefinitely without crashing or exposing any races
or leaks, but I would not bet on that working without bugs in the
core, since that goes beyond the normal pci (device) hotplug case.

	Arnd
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Arnd Bergmann June 14, 2013, 12:53 p.m. UTC | #5
On Friday 14 June 2013 17:18:46 Jingoo Han wrote:
> On Thursday, June 13, 2013 11:14 PM, Arnd Bergmann wrote:
> > On Thursday 13 June 2013 22:22:31 Jingoo Han wrote:

> > > +struct pcie_port {
> > > +	struct device		*dev;
> > > +	u8			controller;
> > > +	u8			root_bus_nr;
> > > +	void __iomem		*dbi_base;
> > > +	void __iomem		*elbi_base;
> > > +	void __iomem		*phy_base;
> > > +	void __iomem		*purple_base;
> > > +	phys_addr_t		cfg0_base;
> > > +	void __iomem		*va_cfg0_base;
> > > +	phys_addr_t		cfg1_base;
> > > +	void __iomem		*va_cfg1_base;
> > > +	phys_addr_t		io_base;
> > > +	phys_addr_t		mem_base;
> > > +	spinlock_t		conf_lock;
> > > +	struct resource		cfg;
> > > +	struct resource		io;
> > > +	struct resource		mem;
> > > +	struct pcie_port_info	config;
> > > +	struct clk		*clk;
> > > +	struct clk		*bus_clk;
> > > +	int			irq;
> > > +	int			reset_gpio;
> > > +};
> > 
> > You mentioned that you'd use u64 for the resources here but did not.
> 
> Do you mean the following?
> 
> +	u64		cfg0_base;
> +	u64		cfg1_base;
> +	u64		io_base;
> +	u64		mem_base;

Yes, anything you need to program into a 64 bit hardware register.

> > > +static void exynos_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
> > > +{
> > > +	u32 val;
> > > +	void __iomem *dbi_base = pp->dbi_base;
> > > +
> > > +	/* Program viewport 1 : OUTBOUND : CFG1 */
> > > +	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
> > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > > +	writel_rc(pp, PCIE_ATU_TYPE_CFG1, dbi_base + PCIE_ATU_CR1);
> > > +	val = PCIE_ATU_ENABLE;
> > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > > +	writel_rc(pp, (u64)pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
> > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > > +	writel_rc(pp, (u64)pp->cfg1_base + pp->config.cfg1_size - 1,
> > > +			dbi_base + PCIE_ATU_LIMIT);
> > > +	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
> > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > > +}
> > 
> > And you still don't set up the UPPER halves, which was really the point
> > of my comment. Same thing for all the other ones.
> 
> Do you mean the following?
> 
> +	writel_rc(pp, pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
> +	writel_rc(pp, (pp->cfg1_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);

Right. Note that you could achieve the same using phys_addr_t instead of
u64, but it's more complicated to get that to work for both 32 and 64 bit
phys_addr_t types, since you cannot shift a 32 bit value by 32 bits in C.

> > > +static void exynos_pcie_prog_viewport_mem_inbound(struct pcie_port *pp)
> > > +{
> > > +	u32 val;
> > > +	void __iomem *dbi_base = pp->dbi_base;
> > > +
> > > +	/* Program viewport 0 : INBOUND : MEM */
> > > +	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX0;
> > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > > +	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
> > > +	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
> > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > > +	writel_rc(pp, (u64)pp->config.mem_bus_addr,
> > > +			dbi_base + PCIE_ATU_LOWER_BASE);
> > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > > +	writel_rc(pp, (u64)pp->config.mem_bus_addr + pp->config.mem_size - 1,
> > > +			dbi_base + PCIE_ATU_LIMIT);
> > > +	writel_rc(pp, (u64)pp->mem_base, dbi_base + PCIE_ATU_LOWER_TARGET);
> > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > > +}
> > 
> > This makes even less sense than before, it seems like now you only
> > allow DMA between PCI devices but not to main memory.
> 
> Sorry, I cannot understand it.
> Could you give me more details?
> Also, pseudo-code will be very helpful.

Please look up the documentation about inbound viewport and describe
in a code comment what it does. I /assume/ that this is how DMA accesses
from the bus get translated into AXI bus transactions. If so, you have
to let the window translate addresses from RAM. If it's something else,
then you should document what it is and how it needs to be set up.
 
> > > +static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
> > > +{
> > > +	struct pcie_port *pp;
> > > +
> > > +	pp = sys_to_pcie(sys);
> > > +
> > > +	if (!pp)
> > > +		return 0;
> > > +
> > > +	pci_add_resource(&sys->resources, &pp->io);
> > > +	pci_add_resource(&sys->resources, &pp->mem);
> > 
> > Now you are missing the offsets. You have to at least pass an offset for one
> > of the I/O spaces, since they are using the same bus address. The offset must
> > match the value you pass to pci_ioremap_io.
> > 
> > For the memory space, you should pass the difference between the physical
> > base address and the bus address. That address happens to be zero with
> > you DT setup, but I would advise to also try out some other values in DT,
> > just to ensure it still works.
> 
> Um, I cannot understand it, too.
> Could you give me Psuedo-code?
> Or, let me know which pcie driver can be the good reference.

I think most hardware is not as flexible as yours, so they can just hardcode
a lot of this.

What you need here is

static unsigned long global_io_offset = 0;
if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
	sys->io_offset = global_io_offset - pp->config.io_bus_addr; /* normally 0 */
	pci_ioremap_io(sys->io_offset, pp->io.start);
	global_io_offset += SZ_64K;
}
sys->mem_offset = pp->mem.start - pp->config.mem_bus_addr; /* normally 0 */

sys->io_offset normally increases by 64K for each bus but should always
be between 0 and 1MB, it is the index into the registers mapped at
(void __iomem*)PCI_IO_VIRT_BASE.

It is best practice to map 64KB of I/O space at bus address 0 for each
domain into PCI_IO_VIRT_BASE, and set up a 1:1 translation between
memory space bus addresses and CPU physical addresses, as you do
in your 'ranges' property.

However, you should be able to use any other bus addresses with the code
above, except for broken device drivers.

> > > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > > +{
> > > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > > +
> > > +	clk_disable_unprepare(pp->bus_clk);
> > > +	clk_disable_unprepare(pp->clk);
> > > +
> > > +	return 0;
> > > +}
> > 
> > You also don't remove the PCI devices here, as mentioned in an earlier
> > review.
> 
> I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
> I cannot know what you mean.
> 
> Could let me know which additional functions are needed?

The mvebu driver does not allow module unload. I haven't looked at the
tegra driver. If you allow unloading the driver and provide a 'remove'
callback, that callback needs to clean up the entire bus and remove
all child devices that were added as well as undo everything the
probe function did. I think it would be great if you can do that, although
it might not be easy. The simplest solution would be to not support
unloading though.

	Arnd
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Jingoo Han June 17, 2013, 9:45 a.m. UTC | #6
On Friday, June 14, 2013 9:54 PM, Arnd Bergmann wrote:
> On Friday 14 June 2013 17:18:46 Jingoo Han wrote:
> > On Thursday, June 13, 2013 11:14 PM, Arnd Bergmann wrote:
> > > On Thursday 13 June 2013 22:22:31 Jingoo Han wrote:
> 
> > > > +struct pcie_port {
> > > > +	struct device		*dev;
> > > > +	u8			controller;
> > > > +	u8			root_bus_nr;
> > > > +	void __iomem		*dbi_base;
> > > > +	void __iomem		*elbi_base;
> > > > +	void __iomem		*phy_base;
> > > > +	void __iomem		*purple_base;
> > > > +	phys_addr_t		cfg0_base;
> > > > +	void __iomem		*va_cfg0_base;
> > > > +	phys_addr_t		cfg1_base;
> > > > +	void __iomem		*va_cfg1_base;
> > > > +	phys_addr_t		io_base;
> > > > +	phys_addr_t		mem_base;
> > > > +	spinlock_t		conf_lock;
> > > > +	struct resource		cfg;
> > > > +	struct resource		io;
> > > > +	struct resource		mem;
> > > > +	struct pcie_port_info	config;
> > > > +	struct clk		*clk;
> > > > +	struct clk		*bus_clk;
> > > > +	int			irq;
> > > > +	int			reset_gpio;
> > > > +};
> > >
> > > You mentioned that you'd use u64 for the resources here but did not.
> >
> > Do you mean the following?
> >
> > +	u64		cfg0_base;
> > +	u64		cfg1_base;
> > +	u64		io_base;
> > +	u64		mem_base;
> 
> Yes, anything you need to program into a 64 bit hardware register.

OK,

> 
> > > > +static void exynos_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
> > > > +{
> > > > +	u32 val;
> > > > +	void __iomem *dbi_base = pp->dbi_base;
> > > > +
> > > > +	/* Program viewport 1 : OUTBOUND : CFG1 */
> > > > +	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
> > > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > > > +	writel_rc(pp, PCIE_ATU_TYPE_CFG1, dbi_base + PCIE_ATU_CR1);
> > > > +	val = PCIE_ATU_ENABLE;
> > > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > > > +	writel_rc(pp, (u64)pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
> > > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > > > +	writel_rc(pp, (u64)pp->cfg1_base + pp->config.cfg1_size - 1,
> > > > +			dbi_base + PCIE_ATU_LIMIT);
> > > > +	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
> > > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > > > +}
> > >
> > > And you still don't set up the UPPER halves, which was really the point
> > > of my comment. Same thing for all the other ones.
> >
> > Do you mean the following?
> >
> > +	writel_rc(pp, pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
> > +	writel_rc(pp, (pp->cfg1_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);
> 
> Right. Note that you could achieve the same using phys_addr_t instead of
> u64, but it's more complicated to get that to work for both 32 and 64 bit
> phys_addr_t types, since you cannot shift a 32 bit value by 32 bits in C.

OK,

> 
> > > > +static void exynos_pcie_prog_viewport_mem_inbound(struct pcie_port *pp)
> > > > +{
> > > > +	u32 val;
> > > > +	void __iomem *dbi_base = pp->dbi_base;
> > > > +
> > > > +	/* Program viewport 0 : INBOUND : MEM */
> > > > +	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX0;
> > > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
> > > > +	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
> > > > +	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
> > > > +	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
> > > > +	writel_rc(pp, (u64)pp->config.mem_bus_addr,
> > > > +			dbi_base + PCIE_ATU_LOWER_BASE);
> > > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
> > > > +	writel_rc(pp, (u64)pp->config.mem_bus_addr + pp->config.mem_size - 1,
> > > > +			dbi_base + PCIE_ATU_LIMIT);
> > > > +	writel_rc(pp, (u64)pp->mem_base, dbi_base + PCIE_ATU_LOWER_TARGET);
> > > > +	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
> > > > +}
> > >
> > > This makes even less sense than before, it seems like now you only
> > > allow DMA between PCI devices but not to main memory.
> >
> > Sorry, I cannot understand it.
> > Could you give me more details?
> > Also, pseudo-code will be very helpful.
> 
> Please look up the documentation about inbound viewport and describe
> in a code comment what it does. I /assume/ that this is how DMA accesses
> from the bus get translated into AXI bus transactions. If so, you have
> to let the window translate addresses from RAM. If it's something else,
> then you should document what it is and how it needs to be set up.

One of our hardware engineer confirmed it.
He said that these inbound functions are unnecessary.
Also, I checked that PCIe works properly without these functions.
So, I will remove these inbound functions.


> 
> > > > +static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
> > > > +{
> > > > +	struct pcie_port *pp;
> > > > +
> > > > +	pp = sys_to_pcie(sys);
> > > > +
> > > > +	if (!pp)
> > > > +		return 0;
> > > > +
> > > > +	pci_add_resource(&sys->resources, &pp->io);
> > > > +	pci_add_resource(&sys->resources, &pp->mem);
> > >
> > > Now you are missing the offsets. You have to at least pass an offset for one
> > > of the I/O spaces, since they are using the same bus address. The offset must
> > > match the value you pass to pci_ioremap_io.
> > >
> > > For the memory space, you should pass the difference between the physical
> > > base address and the bus address. That address happens to be zero with
> > > you DT setup, but I would advise to also try out some other values in DT,
> > > just to ensure it still works.
> >
> > Um, I cannot understand it, too.
> > Could you give me Psuedo-code?
> > Or, let me know which pcie driver can be the good reference.
> 
> I think most hardware is not as flexible as yours, so they can just hardcode
> a lot of this.
> 
> What you need here is
> 
> static unsigned long global_io_offset = 0;
> if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
> 	sys->io_offset = global_io_offset - pp->config.io_bus_addr; /* normally 0 */
> 	pci_ioremap_io(sys->io_offset, pp->io.start);
> 	global_io_offset += SZ_64K;
> }
> sys->mem_offset = pp->mem.start - pp->config.mem_bus_addr; /* normally 0 */
> 
> sys->io_offset normally increases by 64K for each bus but should always
> be between 0 and 1MB, it is the index into the registers mapped at
> (void __iomem*)PCI_IO_VIRT_BASE.
> 
> It is best practice to map 64KB of I/O space at bus address 0 for each
> domain into PCI_IO_VIRT_BASE, and set up a 1:1 translation between
> memory space bus addresses and CPU physical addresses, as you do
> in your 'ranges' property.
> 
> However, you should be able to use any other bus addresses with the code
> above, except for broken device drivers.

Then, do you mean the following?


static unsigned long global_io_offset = 0;

static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
{
	struct pcie_port *pp;

	pp = sys_to_pcie(sys);

	if (!pp)
		return 0;

	if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
		sys->io_offset = global_io_offset - pp->config.io_bus_addr; /* normally 0 */
		pci_ioremap_io(sys->io_offset, pp->io.start);
		global_io_offset += SZ_64K;
	}

	sys->mem_offset = pp->mem.start - pp->config.mem_bus_addr; /* normally 0 */

	pci_add_resource_offset(&sys->resources, &pp->io, sys->io_offset);
	pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset);

        return 1;
}

In this case, boot message is as below:

PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [io  0x40001000-0x40010fff]
pci_bus 0000:00: root bus resource [mem 0x40011000-0x5fffffff]
pci_bus 0000:00: No busn resource found for root bus, will use [bus 00-ff]
pci 0000:00:00.0: [144d:a549] type 01 class 0x060400
[.....]
PCI host bridge to bus 0001:00
pci_bus 0001:00: root bus resource [io  0x60001000-0x60010fff] (bus address [0x5fff1000-0x6000
0fff])
pci_bus 0001:00: root bus resource [mem 0x60011000-0x7fffffff]
pci_bus 0001:00: No busn resource found for root bus, will use [bus 00-ff]
pci 0001:00:00.0: [144d:a549] type 01 class 0x060400

> 
> > > > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > > > +{
> > > > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > > > +
> > > > +	clk_disable_unprepare(pp->bus_clk);
> > > > +	clk_disable_unprepare(pp->clk);
> > > > +
> > > > +	return 0;
> > > > +}
> > >
> > > You also don't remove the PCI devices here, as mentioned in an earlier
> > > review.
> >
> > I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
> > I cannot know what you mean.
> >
> > Could let me know which additional functions are needed?
> 
> The mvebu driver does not allow module unload. I haven't looked at the
> tegra driver. If you allow unloading the driver and provide a 'remove'
> callback, that callback needs to clean up the entire bus and remove
> all child devices that were added as well as undo everything the
> probe function did. I think it would be great if you can do that, although
> it might not be easy. The simplest solution would be to not support
> unloading though.

As the mvebu driver uses platform_driver_probe(), the Exynos driver uses
platform_driver_probe(). Thus, I will not provide a 'remove' callback.

Thank you.

Best regards,
Jingoo Han

> 
> 	Arnd

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Arnd Bergmann June 17, 2013, 12:44 p.m. UTC | #7
On Monday 17 June 2013 18:45:52 Jingoo Han wrote:
> On Friday, June 14, 2013 9:54 PM, Arnd Bergmann wrote:
> > 
> > Please look up the documentation about inbound viewport and describe
> > in a code comment what it does. I /assume/ that this is how DMA accesses
> > from the bus get translated into AXI bus transactions. If so, you have
> > to let the window translate addresses from RAM. If it's something else,
> > then you should document what it is and how it needs to be set up.
> 
> One of our hardware engineer confirmed it.
> He said that these inbound functions are unnecessary.
> Also, I checked that PCIe works properly without these functions.
> So, I will remove these inbound functions.

Ok, good. So DMA just gets translated 1:1 independent of the
inbound viewport? Have you tested this with PCI device using
DMA?

> static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
> {
> 	struct pcie_port *pp;
> 
> 	pp = sys_to_pcie(sys);
> 
> 	if (!pp)
> 		return 0;
> 
> 	if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
> 		sys->io_offset = global_io_offset - pp->config.io_bus_addr; /* normally 0 */
> 		pci_ioremap_io(sys->io_offset, pp->io.start);
> 		global_io_offset += SZ_64K;
> 	}
> 
> 	sys->mem_offset = pp->mem.start - pp->config.mem_bus_addr; /* normally 0 */
> 
> 	pci_add_resource_offset(&sys->resources, &pp->io, sys->io_offset);
> 	pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset);
> 
>         return 1;
> }

This is what I meant, yes.

> In this case, boot message is as below:
> 
> PCI host bridge to bus 0000:00
> pci_bus 0000:00: root bus resource [io  0x40001000-0x40010fff]
> pci_bus 0000:00: root bus resource [mem 0x40011000-0x5fffffff]
> pci_bus 0000:00: No busn resource found for root bus, will use [bus 00-ff]
> pci 0000:00:00.0: [144d:a549] type 01 class 0x060400
> [.....]
> PCI host bridge to bus 0001:00
> pci_bus 0001:00: root bus resource [io  0x60001000-0x60010fff] (bus address [0x5fff1000-0x6000
> 0fff])
> pci_bus 0001:00: root bus resource [mem 0x60011000-0x7fffffff]
> pci_bus 0001:00: No busn resource found for root bus, will use [bus 00-ff]
> pci 0001:00:00.0: [144d:a549] type 01 class 0x060400

The io resources here look wrong. I would have expected

pci_bus 0000:00: root bus resource [io  0x001000-0x00ffff]
pci_bus 0001:00: root bus resource [io  0x010000-0x01ffff] (bus address [0x000000-0x00ffff])

Please have a look at the pci-mvebu driver and how it calculates its
'realio' resource.

> > > > > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > > > > +{
> > > > > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > > > > +
> > > > > +	clk_disable_unprepare(pp->bus_clk);
> > > > > +	clk_disable_unprepare(pp->clk);
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > >
> > > > You also don't remove the PCI devices here, as mentioned in an earlier
> > > > review.
> > >
> > > I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
> > > I cannot know what you mean.
> > >
> > > Could let me know which additional functions are needed?
> > 
> > The mvebu driver does not allow module unload. I haven't looked at the
> > tegra driver. If you allow unloading the driver and provide a 'remove'
> > callback, that callback needs to clean up the entire bus and remove
> > all child devices that were added as well as undo everything the
> > probe function did. I think it would be great if you can do that, although
> > it might not be easy. The simplest solution would be to not support
> > unloading though.
> 
> As the mvebu driver uses platform_driver_probe(), the Exynos driver uses
> platform_driver_probe(). Thus, I will not provide a 'remove' callback.

Well, the important part is not to provide a module_exit() function, which
will ensure the driver cannot be unloaded.

	Arnd
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Jingoo Han June 18, 2013, 3:52 a.m. UTC | #8
On Monday, June 17, 2013 9:45 PM, Arnd Bergmann wrote:
> On Monday 17 June 2013 18:45:52 Jingoo Han wrote:
> > On Friday, June 14, 2013 9:54 PM, Arnd Bergmann wrote:
> > >
> > > Please look up the documentation about inbound viewport and describe
> > > in a code comment what it does. I /assume/ that this is how DMA accesses
> > > from the bus get translated into AXI bus transactions. If so, you have
> > > to let the window translate addresses from RAM. If it's something else,
> > > then you should document what it is and how it needs to be set up.
> >
> > One of our hardware engineer confirmed it.
> > He said that these inbound functions are unnecessary.
> > Also, I checked that PCIe works properly without these functions.
> > So, I will remove these inbound functions.
> 
> Ok, good. So DMA just gets translated 1:1 independent of the
> inbound viewport? Have you tested this with PCI device using
> DMA?

According to our hardware engineer,
He said that
"That's correct. We tested it by doing a memory write from the device.
A device DMA is a series of memory r/w so I expect it to work same way."

Also, he thought that I already tested too, since it works after removing
the functions.

> 
> > static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
> > {
> > 	struct pcie_port *pp;
> >
> > 	pp = sys_to_pcie(sys);
> >
> > 	if (!pp)
> > 		return 0;
> >
> > 	if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
> > 		sys->io_offset = global_io_offset - pp->config.io_bus_addr; /* normally 0 */
> > 		pci_ioremap_io(sys->io_offset, pp->io.start);
> > 		global_io_offset += SZ_64K;
> > 	}
> >
> > 	sys->mem_offset = pp->mem.start - pp->config.mem_bus_addr; /* normally 0 */
> >
> > 	pci_add_resource_offset(&sys->resources, &pp->io, sys->io_offset);
> > 	pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset);
> >
> >         return 1;
> > }
> 
> This is what I meant, yes.
> 
> > In this case, boot message is as below:
> >
> > PCI host bridge to bus 0000:00
> > pci_bus 0000:00: root bus resource [io  0x40001000-0x40010fff]
> > pci_bus 0000:00: root bus resource [mem 0x40011000-0x5fffffff]
> > pci_bus 0000:00: No busn resource found for root bus, will use [bus 00-ff]
> > pci 0000:00:00.0: [144d:a549] type 01 class 0x060400
> > [.....]
> > PCI host bridge to bus 0001:00
> > pci_bus 0001:00: root bus resource [io  0x60001000-0x60010fff] (bus address [0x5fff1000-0x6000
> > 0fff])
> > pci_bus 0001:00: root bus resource [mem 0x60011000-0x7fffffff]
> > pci_bus 0001:00: No busn resource found for root bus, will use [bus 00-ff]
> > pci 0001:00:00.0: [144d:a549] type 01 class 0x060400
> 
> The io resources here look wrong. I would have expected
> 
> pci_bus 0000:00: root bus resource [io  0x001000-0x00ffff]
> pci_bus 0001:00: root bus resource [io  0x010000-0x01ffff] (bus address [0x000000-0x00ffff])
> 
> Please have a look at the pci-mvebu driver and how it calculates its
> 'realio' resource.

I looked at the pci-mvebu driver,
Then I fixed it as the pci-mvebu driver did.
Also, I added 'global_io_offset'.

@@ -909,6 +909,12 @@ static int __init exynos_pcie_probe(struct platform_device *pdev)
                if (restype == IORESOURCE_IO) {
                        of_pci_range_to_resource(&range, np, &pp->io);
                        pp->io.name = "I/O";
+                       pp->io.start = max_t(resource_size_t,
+                                               PCIBIOS_MIN_IO,
+                                               range.pci_addr + global_io_offset);
+                       pp->io.end = min_t(resource_size_t,
+                                               IO_SPACE_LIMIT,
+                                               range.pci_addr + range.size + global_io_offset);
                        pp->config.io_size = resource_size(&pp->io);
                        pp->config.io_bus_addr = range.pci_addr;

In this case, boot message is as below:

PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [io  0x1000-0x10000]
pci_bus 0000:00: root bus resource [mem 0x40011000-0x5fffffff]
[.....]
PCI host bridge to bus 0001:00
pci_bus 0001:00: root bus resource [io  0x10000-0x20000] (bus address [0x0000-0x10000])
pci_bus 0001:00: root bus resource [mem 0x60011000-0x7fffffff]



> 
> > > > > > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > > > > > +{
> > > > > > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > > > > > +
> > > > > > +	clk_disable_unprepare(pp->bus_clk);
> > > > > > +	clk_disable_unprepare(pp->clk);
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > >
> > > > > You also don't remove the PCI devices here, as mentioned in an earlier
> > > > > review.
> > > >
> > > > I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
> > > > I cannot know what you mean.
> > > >
> > > > Could let me know which additional functions are needed?
> > >
> > > The mvebu driver does not allow module unload. I haven't looked at the
> > > tegra driver. If you allow unloading the driver and provide a 'remove'
> > > callback, that callback needs to clean up the entire bus and remove
> > > all child devices that were added as well as undo everything the
> > > probe function did. I think it would be great if you can do that, although
> > > it might not be easy. The simplest solution would be to not support
> > > unloading though.
> >
> > As the mvebu driver uses platform_driver_probe(), the Exynos driver uses
> > platform_driver_probe(). Thus, I will not provide a 'remove' callback.
> 
> Well, the important part is not to provide a module_exit() function, which
> will ensure the driver cannot be unloaded.

I will remove a 'remove' callback. Is it OK?
Or what should I do?


Thank you for your comment. :)

Best regards,
Jingoo Han

> 
> 	Arnd

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Jingoo Han June 18, 2013, 5:35 a.m. UTC | #9
On Monday, June 17, 2013 9:45 PM, Arnd Bergmann wrote:
> On Monday 17 June 2013 18:45:52 Jingoo Han wrote:
> > On Friday, June 14, 2013 9:54 PM, Arnd Bergmann wrote:
> > >
[.....]
> > > > > > +static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > > > > > +{
> > > > > > +	struct pcie_port *pp = platform_get_drvdata(pdev);
> > > > > > +
> > > > > > +	clk_disable_unprepare(pp->bus_clk);
> > > > > > +	clk_disable_unprepare(pp->clk);
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > >
> > > > > You also don't remove the PCI devices here, as mentioned in an earlier
> > > > > review.
> > > >
> > > > I reviewed Marvell PCIe driver and Tegra PCIe driver; however,
> > > > I cannot know what you mean.
> > > >
> > > > Could let me know which additional functions are needed?
> > >
> > > The mvebu driver does not allow module unload. I haven't looked at the
> > > tegra driver. If you allow unloading the driver and provide a 'remove'
> > > callback, that callback needs to clean up the entire bus and remove
> > > all child devices that were added as well as undo everything the
> > > probe function did. I think it would be great if you can do that, although
> > > it might not be easy. The simplest solution would be to not support
> > > unloading though.
> >
> > As the mvebu driver uses platform_driver_probe(), the Exynos driver uses
> > platform_driver_probe(). Thus, I will not provide a 'remove' callback.
> 
> Well, the important part is not to provide a module_exit() function, which
> will ensure the driver cannot be unloaded.

Aha, I see.
I will not provide a module_exit() function), as the mvebu driver does.

Best regards,
Jingoo Han

> 
> 	Arnd

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Arnd Bergmann June 18, 2013, 1:56 p.m. UTC | #10
On Tuesday 18 June 2013, Jingoo Han wrote:
> On Monday, June 17, 2013 9:45 PM, Arnd Bergmann wrote:
> > On Monday 17 June 2013 18:45:52 Jingoo Han wrote:
> > > On Friday, June 14, 2013 9:54 PM, Arnd Bergmann wrote:
> > > >
> > > > Please look up the documentation about inbound viewport and describe
> > > > in a code comment what it does. I /assume/ that this is how DMA accesses
> > > > from the bus get translated into AXI bus transactions. If so, you have
> > > > to let the window translate addresses from RAM. If it's something else,
> > > > then you should document what it is and how it needs to be set up.
> > >
> > > One of our hardware engineer confirmed it.
> > > He said that these inbound functions are unnecessary.
> > > Also, I checked that PCIe works properly without these functions.
> > > So, I will remove these inbound functions.
> > 
> > Ok, good. So DMA just gets translated 1:1 independent of the
> > inbound viewport? Have you tested this with PCI device using
> > DMA?
> 
> According to our hardware engineer,
> He said that
> "That's correct. We tested it by doing a memory write from the device.
> A device DMA is a series of memory r/w so I expect it to work same way."
> 
> Also, he thought that I already tested too, since it works after removing
> the functions.

It could be that the default setting just creates a 1:1 map so that would
work, but if you tested it, that should be good enough.

> I looked at the pci-mvebu driver,
> Then I fixed it as the pci-mvebu driver did.
> Also, I added 'global_io_offset'.
> 
> @@ -909,6 +909,12 @@ static int __init exynos_pcie_probe(struct platform_device *pdev)
>                 if (restype == IORESOURCE_IO) {
>                         of_pci_range_to_resource(&range, np, &pp->io);
>                         pp->io.name = "I/O";
> +                       pp->io.start = max_t(resource_size_t,
> +                                               PCIBIOS_MIN_IO,
> +                                               range.pci_addr + global_io_offset);
> +                       pp->io.end = min_t(resource_size_t,
> +                                               IO_SPACE_LIMIT,
> +                                               range.pci_addr + range.size + global_io_offset);
>                         pp->config.io_size = resource_size(&pp->io);
>                         pp->config.io_bus_addr = range.pci_addr;
> 
> In this case, boot message is as below:
> 
> PCI host bridge to bus 0000:00
> pci_bus 0000:00: root bus resource [io  0x1000-0x10000]
> pci_bus 0000:00: root bus resource [mem 0x40011000-0x5fffffff]
> [.....]
> PCI host bridge to bus 0001:00
> pci_bus 0001:00: root bus resource [io  0x10000-0x20000] (bus address [0x0000-0x10000])
> pci_bus 0001:00: root bus resource [mem 0x60011000-0x7fffffff]

Ok, very good.
> 
> I will remove a 'remove' callback. Is it OK?
> Or what should I do?

I think you should keep the remove function, but add a comment explaining that
you don't allow module unload and that in order to allow it, the remove function
will have to remove all pci buses and devices under the host bridge.

	Arnd
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Jingoo Han June 19, 2013, 1:13 a.m. UTC | #11
On Tuesday, June 18, 2013 10:57 PM, Arnd Bergmann wrote:
> On Tuesday 18 June 2013, Jingoo Han wrote:
> > On Monday, June 17, 2013 9:45 PM, Arnd Bergmann wrote:
> > > On Monday 17 June 2013 18:45:52 Jingoo Han wrote:
> > > > On Friday, June 14, 2013 9:54 PM, Arnd Bergmann wrote:
> > > > >

[.....]

> >
> > I will remove a 'remove' callback. Is it OK?
> > Or what should I do?
> 
> I think you should keep the remove function, but add a comment explaining that
> you don't allow module unload and that in order to allow it, the remove function
> will have to remove all pci buses and devices under the host bridge.

Then, do you mean the following?

static int __exit exynos_pcie_remove(struct platform_device *pdev)
{
	struct pcie_port *pp = platform_get_drvdata(pdev);

	clk_disable_unprepare(pp->bus_clk);
	clk_disable_unprepare(pp->clk);

	return 0;
}

static struct platform_driver exynos_pcie_driver = {
	.remove	= __exit_p(exynos_pcie_remove),

[.....]

/* Exynos PCIe driver does not allow module unload */

static int __init pcie_init(void)
{
	hook_fault_code(16 + 6, exynos_pcie_abort, SIGBUS, 0,
			"imprecise external abort");

	platform_driver_probe(&exynos_pcie_driver, exynos_pcie_probe);

	return 0;
}
subsys_initcall(pcie_init);

MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
MODULE_DESCRIPTION("Samsung PCIe host controller driver");
MODULE_LICENSE("GPLv2");


> 
> 	Arnd
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Arnd Bergmann June 19, 2013, 12:43 p.m. UTC | #12
On Wednesday 19 June 2013, Jingoo Han wrote:
> Then, do you mean the following?
> 
> static int __exit exynos_pcie_remove(struct platform_device *pdev)
> {
>         struct pcie_port *pp = platform_get_drvdata(pdev);
> 
>         clk_disable_unprepare(pp->bus_clk);
>         clk_disable_unprepare(pp->clk);
> 
>         return 0;
> }
> 
> static struct platform_driver exynos_pcie_driver = {
>         .remove = __exit_p(exynos_pcie_remove),
> 
> [.....]
> 
> /* Exynos PCIe driver does not allow module unload */
> 
> static int __init pcie_init(void)
> {
>         hook_fault_code(16 + 6, exynos_pcie_abort, SIGBUS, 0,
>                         "imprecise external abort");
> 
>         platform_driver_probe(&exynos_pcie_driver, exynos_pcie_probe);
> 
>         return 0;
> }
> subsys_initcall(pcie_init);
> 
> MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
> MODULE_DESCRIPTION("Samsung PCIe host controller driver");
> MODULE_LICENSE("GPLv2");
> 

Yes, this looks good. I would probably use platform_driver_register
rather than platform_driver_probe, but that is your choice. using
platform_driver_probe() mean you cannot deal with deferred probing.

	Arnd
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Jingoo Han June 20, 2013, 6:41 a.m. UTC | #13
On Wednesday, June 19, 2013 9:43 PM, Arnd Bergmann wrote:
> On Wednesday 19 June 2013, Jingoo Han wrote:
> > Then, do you mean the following?
> >
> > static int __exit exynos_pcie_remove(struct platform_device *pdev)
> > {
> >         struct pcie_port *pp = platform_get_drvdata(pdev);
> >
> >         clk_disable_unprepare(pp->bus_clk);
> >         clk_disable_unprepare(pp->clk);
> >
> >         return 0;
> > }
> >
> > static struct platform_driver exynos_pcie_driver = {
> >         .remove = __exit_p(exynos_pcie_remove),
> >
> > [.....]
> >
> > /* Exynos PCIe driver does not allow module unload */
> >
> > static int __init pcie_init(void)
> > {
> >         hook_fault_code(16 + 6, exynos_pcie_abort, SIGBUS, 0,
> >                         "imprecise external abort");
> >
> >         platform_driver_probe(&exynos_pcie_driver, exynos_pcie_probe);
> >
> >         return 0;
> > }
> > subsys_initcall(pcie_init);
> >
> > MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
> > MODULE_DESCRIPTION("Samsung PCIe host controller driver");
> > MODULE_LICENSE("GPLv2");
> >
> 
> Yes, this looks good. I would probably use platform_driver_register
> rather than platform_driver_probe, but that is your choice. using
> platform_driver_probe() mean you cannot deal with deferred probing.

Hi Arnd,

Thank you for your reply. :)
I will send PATCH v6, soon.
I really appreciate your comments.

Hi Thomas Abraham, Kukjin Kim,
Thank you for your support.
It is very helpful.


Best regards,
Jingoo Han


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Thierry Reding July 17, 2013, 5:07 a.m. UTC | #14
On Fri, Jun 14, 2013 at 02:38:49PM +0200, Arnd Bergmann wrote:
> On Friday 14 June 2013 12:53:11 Thierry Reding wrote:
> > 
> > I think the biggest missing piece is pci_common_exit(), the counterpart
> > of pci_common_init(), to cleanup a host bridge on ARM. I haven't looked
> > in detail at the other architectures, but I suspect there must be some
> > code to call when a host bridge is removed.
> > 
> > Looking at drivers/pci/remove.c, it seems like pci_remove_root_bus()
> > might be what we're looking at. It isn't exported so it can't be used by
> > modules, but that can be changed. Is that how a host bridge is typically
> > removed from the system?
> 
> It's fairly new to have host bridges in loadable modules, so I'm pretty
> sure it's not supported by the core yet, but it also doesn't seem hard
> to do. I think you are right with regard to pci_remove_root_bus,
> and Bjorn might be able to provide more information.
> 
> Ideally we should be able to load and unload the pci host driver
> in a loop indefinitely without crashing or exposing any races
> or leaks, but I would not bet on that working without bugs in the
> core, since that goes beyond the normal pci (device) hotplug case.

I've done some preliminary testing on Tegra using sysfs to unbind and
rebind the device from and to the driver. Some code needs to be added
for this to work, but it doesn't crash and PCI even continues to work
after unbinding and rebinding (tested using gigabit ethernet).

However I haven't looked for leaks yet, and I'm pretty sure some more
code is required to undo some of what pci_common_init() does on ARM.
Looking more closely, I think most (if not all) remaining leaks could
be fixed by keeping the list of pci_sys_data structures around and
cleaning them up properly.

Given the experimental nature of this I don't want to make that part of
the driver for 3.12 and I've opted to just disable any means of removing
the driver for now. But I do want to get back to this after the driver
has been merged.

Thierry
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/pci/exynos-pcie.txt b/Documentation/devicetree/bindings/pci/exynos-pcie.txt
new file mode 100644
index 0000000..638e68c
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/exynos-pcie.txt
@@ -0,0 +1,71 @@ 
+* Samsung Exynos PCIe interface
+
+Required properties:
+-compatible: should be "samsung,exynos5440-pcie"
+-reg: base addresses and lengths of the pcie conteroller,
+	the phy controller, additional register for the phy controller.
+- interrupts: interrupt values for level interrupt,
+	pulse interrupt, special interrupt.
+- clocks: from common clock binding: handle to pci clock.
+- clock-names: from common clock binding: Shall be "pcie", "pcie_bus".
+- #address-cells: set to <3>
+- #size-cells: set to <2>
+- device_type: set to "pci"
+- ranges: ranges for the PCI memory and I/O regions
+- #interrupt-cells: set to <1>
+- interrupt-map-mask and interrupt-map: standard PCI properties
+	to define the mapping of the PCIe interface to interrupt
+	numbers.
+- reset-gpio: gpio pin number of power good signal
+
+Example:
+
+SoC specific DT Entry:
+
+	pcie0@290000 {
+		compatible = "samsung,exynos5440-pcie";
+		reg = <0x290000 0x1000
+			0x270000 0x1000
+			0x271000 0x40>;
+		interrupts = <0 20 0>, <0 21 0>, <0 22 0>;
+		clocks = <&clock 28>, <&clock 27>;
+		clock-names = "pcie", "pcie_bus";
+		#address-cells = <3>;
+		#size-cells = <2>;
+		device_type = "pci";
+		ranges = <0x00000800 0 0x40000000 0x40000000 0 0x00001000   /* configuration space */
+			  0x81000000 0 0	  0x40001000 0 0x00010000   /* downstream I/O */
+			  0x82000000 0 0x40011000 0x40011000 0 0x1ffef000>; /* non-prefetchable memory */
+		#interrupt-cells = <1>;
+		interrupt-map-mask = <0 0 0 0>;
+		interrupt-map = <0x0 0 &gic 53>;
+	};
+
+	pcie1@2a0000 {
+		compatible = "samsung,exynos5440-pcie";
+		reg = <0x2a0000 0x1000
+			0x272000 0x1000
+			0x271040 0x40>;
+		interrupts = <0 23 0>, <0 24 0>, <0 25 0>;
+		clocks = <&clock 29>, <&clock 27>;
+		clock-names = "pcie", "pcie_bus";
+		#address-cells = <3>;
+		#size-cells = <2>;
+		device_type = "pci";
+		ranges = <0x00000800 0 0x60000000 0x60000000 0 0x00001000   /* configuration space */
+			  0x81000000 0 0	  0x60001000 0 0x00010000   /* downstream I/O */
+			  0x82000000 0 0x60011000 0x60011000 0 0x1ffef000>; /* non-prefetchable memory */
+		#interrupt-cells = <1>;
+		interrupt-map-mask = <0 0 0 0>;
+		interrupt-map = <0x0 0 &gic 56>;
+	};
+
+Board specific DT Entry:
+
+	pcie0@290000 {
+		reset-gpio = <&pin_ctrl 5 0>;
+	};
+
+	pcie1@2a0000 {
+		reset-gpio = <&pin_ctrl 22 0>;
+	};
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 1f1d67f..fec0f1f 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -5,4 +5,9 @@  config PCI_MVEBU
 	bool "Marvell EBU PCIe controller"
 	depends on ARCH_MVEBU || ARCH_KIRKWOOD
 
+config PCI_EXYNOS
+	bool "Samsung Exynos PCIe controller"
+	depends on SOC_EXYNOS5440
+	select PCIEPORTBUS
+
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 5ea2d8b..31d77ad 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -1 +1,2 @@ 
 obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
+obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c
new file mode 100644
index 0000000..abfa3dc
--- /dev/null
+++ b/drivers/pci/host/pci-exynos.c
@@ -0,0 +1,1078 @@ 
+/*
+ * PCIe host controller driver for Samsung EXYNOS SoCs
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Author: Jingoo Han <jg1.han@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_gpio.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+struct pcie_port_info {
+	u32		cfg0_size;
+	u32		cfg1_size;
+	u32		io_size;
+	u32		mem_size;
+	phys_addr_t	io_bus_addr;
+	phys_addr_t	mem_bus_addr;
+};
+
+struct pcie_port {
+	struct device		*dev;
+	u8			controller;
+	u8			root_bus_nr;
+	void __iomem		*dbi_base;
+	void __iomem		*elbi_base;
+	void __iomem		*phy_base;
+	void __iomem		*purple_base;
+	phys_addr_t		cfg0_base;
+	void __iomem		*va_cfg0_base;
+	phys_addr_t		cfg1_base;
+	void __iomem		*va_cfg1_base;
+	phys_addr_t		io_base;
+	phys_addr_t		mem_base;
+	spinlock_t		conf_lock;
+	struct resource		cfg;
+	struct resource		io;
+	struct resource		mem;
+	struct pcie_port_info	config;
+	struct clk		*clk;
+	struct clk		*bus_clk;
+	int			irq;
+	int			reset_gpio;
+};
+
+/* synopsis specific PCIE configuration registers*/
+#define PCIE_PORT_LINK_CONTROL		0x710
+#define PORT_LINK_MODE_MASK		(0x3f << 16)
+#define PORT_LINK_MODE_4_LANES		(0x7 << 16)
+
+#define PCIE_LINK_WIDTH_SPEED_CONTROL	0x80C
+#define PORT_LOGIC_SPEED_CHANGE		(0x1 << 17)
+#define PORT_LOGIC_LINK_WIDTH_MASK	(0x1ff << 8)
+#define PORT_LOGIC_LINK_WIDTH_4_LANES	(0x7 << 8)
+
+#define PCIE_MSI_ADDR_LO		0x820
+#define PCIE_MSI_ADDR_HI		0x824
+#define PCIE_MSI_INTR0_ENABLE		0x828
+#define PCIE_MSI_INTR0_MASK		0x82C
+#define PCIE_MSI_INTR0_STATUS		0x830
+
+#define PCIE_ATU_VIEWPORT		0x900
+#define PCIE_ATU_REGION_INBOUND		(0x1 << 31)
+#define PCIE_ATU_REGION_OUTBOUND	(0x0 << 31)
+#define PCIE_ATU_REGION_INDEX1		(0x1 << 0)
+#define PCIE_ATU_REGION_INDEX0		(0x0 << 0)
+#define PCIE_ATU_CR1			0x904
+#define PCIE_ATU_TYPE_MEM		(0x0 << 0)
+#define PCIE_ATU_TYPE_IO		(0x2 << 0)
+#define PCIE_ATU_TYPE_CFG0		(0x4 << 0)
+#define PCIE_ATU_TYPE_CFG1		(0x5 << 0)
+#define PCIE_ATU_CR2			0x908
+#define PCIE_ATU_ENABLE			(0x1 << 31)
+#define PCIE_ATU_BAR_MODE_ENABLE	(0x1 << 30)
+#define PCIE_ATU_LOWER_BASE		0x90C
+#define PCIE_ATU_UPPER_BASE		0x910
+#define PCIE_ATU_LIMIT			0x914
+#define PCIE_ATU_LOWER_TARGET		0x918
+#define PCIE_ATU_BUS(x)			(((x) & 0xff) << 24)
+#define PCIE_ATU_DEV(x)			(((x) & 0x1f) << 19)
+#define PCIE_ATU_FUNC(x)		(((x) & 0x7) << 16)
+#define PCIE_ATU_UPPER_TARGET		0x91C
+
+/* PCIe ELBI registers */
+#define PCIE_IRQ_PULSE			0x000
+#define IRQ_INTA_ASSERT			(0x1 << 0)
+#define IRQ_INTB_ASSERT			(0x1 << 2)
+#define IRQ_INTC_ASSERT			(0x1 << 4)
+#define IRQ_INTD_ASSERT			(0x1 << 6)
+#define PCIE_IRQ_LEVEL			0x004
+#define PCIE_IRQ_SPECIAL		0x008
+#define PCIE_IRQ_EN_PULSE		0x00c
+#define PCIE_IRQ_EN_LEVEL		0x010
+#define PCIE_IRQ_EN_SPECIAL		0x014
+#define PCIE_PWR_RESET			0x018
+#define PCIE_CORE_RESET			0x01c
+#define PCIE_CORE_RESET_ENABLE		(0x1 << 0)
+#define PCIE_STICKY_RESET		0x020
+#define PCIE_NONSTICKY_RESET		0x024
+#define PCIE_APP_INIT_RESET		0x028
+#define PCIE_APP_LTSSM_ENABLE		0x02c
+#define PCIE_ELBI_RDLH_LINKUP		0x064
+#define PCIE_ELBI_LTSSM_ENABLE		0x1
+#define PCIE_ELBI_SLV_AWMISC		0x11c
+#define PCIE_ELBI_SLV_ARMISC		0x120
+#define PCIE_ELBI_SLV_DBI_ENABLE	(0x1 << 21)
+
+/* PCIe Purple registers */
+#define PCIE_PHY_GLOBAL_RESET		0x000
+#define PCIE_PHY_COMMON_RESET		0x004
+#define PCIE_PHY_CMN_REG		0x008
+#define PCIE_PHY_MAC_RESET		0x00c
+#define PCIE_PHY_PLL_LOCKED		0x010
+#define PCIE_PHY_TRSVREG_RESET		0x020
+#define PCIE_PHY_TRSV_RESET		0x024
+
+/* PCIe PHY registers */
+#define PCIE_PHY_IMPEDANCE		0x004
+#define PCIE_PHY_PLL_DIV_0		0x008
+#define PCIE_PHY_PLL_BIAS		0x00c
+#define PCIE_PHY_DCC_FEEDBACK		0x014
+#define PCIE_PHY_PLL_DIV_1		0x05c
+#define PCIE_PHY_TRSV0_EMP_LVL		0x084
+#define PCIE_PHY_TRSV0_DRV_LVL		0x088
+#define PCIE_PHY_TRSV0_RXCDR		0x0ac
+#define PCIE_PHY_TRSV0_LVCC		0x0dc
+#define PCIE_PHY_TRSV1_EMP_LVL		0x144
+#define PCIE_PHY_TRSV1_RXCDR		0x16c
+#define PCIE_PHY_TRSV1_LVCC		0x19c
+#define PCIE_PHY_TRSV2_EMP_LVL		0x204
+#define PCIE_PHY_TRSV2_RXCDR		0x22c
+#define PCIE_PHY_TRSV2_LVCC		0x25c
+#define PCIE_PHY_TRSV3_EMP_LVL		0x2c4
+#define PCIE_PHY_TRSV3_RXCDR		0x2ec
+#define PCIE_PHY_TRSV3_LVCC		0x31c
+
+static struct hw_pci exynos_pci;
+
+static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
+{
+	return sys->private_data;
+}
+
+static inline int cfg_read(void *addr, int where, int size, u32 *val)
+{
+	*val = readl(addr);
+
+	if (size == 1)
+		*val = (*val >> (8 * (where & 3))) & 0xff;
+	else if (size == 2)
+		*val = (*val >> (8 * (where & 3))) & 0xffff;
+	else if (size != 4)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static inline int cfg_write(void *addr, int where, int size, u32 val)
+{
+	if (size == 4)
+		writel(val, addr);
+	else if (size == 2)
+		writew(val, addr + (where & 2));
+	else if (size == 1)
+		writeb(val, addr + (where & 3));
+	else
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static void exynos_pcie_sideband_dbi_w_mode(struct pcie_port *pp, bool on)
+{
+	u32 val;
+
+	if (on) {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+		val |= PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+	} else {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+		val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+	}
+}
+
+static void exynos_pcie_sideband_dbi_r_mode(struct pcie_port *pp, bool on)
+{
+	u32 val;
+
+	if (on) {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+		val |= PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+	} else {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+		val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+	}
+}
+
+static inline void readl_rc(struct pcie_port *pp, void *dbi_base, u32 *val)
+{
+	exynos_pcie_sideband_dbi_r_mode(pp, true);
+	*val = readl(dbi_base);
+	exynos_pcie_sideband_dbi_r_mode(pp, false);
+	return;
+}
+
+static inline void writel_rc(struct pcie_port *pp, u32 val, void *dbi_base)
+{
+	exynos_pcie_sideband_dbi_w_mode(pp, true);
+	writel(val, dbi_base);
+	exynos_pcie_sideband_dbi_w_mode(pp, false);
+	return;
+}
+
+static int exynos_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
+		u32 *val)
+{
+	int ret;
+
+	exynos_pcie_sideband_dbi_r_mode(pp, true);
+	ret = cfg_read(pp->dbi_base + (where & ~0x3), where, size, val);
+	exynos_pcie_sideband_dbi_r_mode(pp, false);
+	return ret;
+}
+
+static int exynos_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
+		u32 val)
+{
+	int ret;
+
+	exynos_pcie_sideband_dbi_w_mode(pp, true);
+	ret = cfg_write(pp->dbi_base + (where & ~0x3), where, size, val);
+	exynos_pcie_sideband_dbi_w_mode(pp, false);
+	return ret;
+}
+
+static void exynos_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32 busdev)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 0 : OUTBOUND : CFG0 */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, (u64)pp->cfg0_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, (u64)pp->cfg0_base + pp->config.cfg0_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+	writel_rc(pp, PCIE_ATU_TYPE_CFG0, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+}
+
+static void exynos_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 1 : OUTBOUND : CFG1 */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_CFG1, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, (u64)pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, (u64)pp->cfg1_base + pp->config.cfg1_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static void exynos_pcie_prog_viewport_mem_outbound(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 0 : OUTBOUND : MEM */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, (u64)pp->mem_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, (u64)pp->mem_base + pp->config.mem_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, (u64)pp->config.mem_bus_addr,
+			dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static void exynos_pcie_prog_viewport_io_outbound(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 1 : OUTBOUND : IO */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_IO, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, (u64)pp->io_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, (u64)pp->io_base + pp->config.io_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, (u64)pp->config.io_bus_addr,
+			dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static void exynos_pcie_prog_viewport_mem_inbound(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 0 : INBOUND : MEM */
+	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX0;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, (u64)pp->config.mem_bus_addr,
+			dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, (u64)pp->config.mem_bus_addr + pp->config.mem_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, (u64)pp->mem_base, dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static void exynos_pcie_prog_viewport_io_inbound(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 1 : INBOUND : IO */
+	val = PCIE_ATU_REGION_INBOUND | PCIE_ATU_REGION_INDEX1;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_IO, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE | PCIE_ATU_BAR_MODE_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, (u64)pp->config.io_bus_addr,
+			dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, (u64)pp->config.io_bus_addr + pp->config.io_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, (u64)pp->io_base, dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static int exynos_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+		u32 devfn, int where, int size, u32 *val)
+{
+	int ret = PCIBIOS_SUCCESSFUL;
+	u32 address, busdev;
+
+	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
+		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
+	address = where & ~0x3;
+
+	if (bus->parent->number == pp->root_bus_nr) {
+		exynos_pcie_prog_viewport_cfg0(pp, busdev);
+		ret = cfg_read(pp->va_cfg0_base + address, where, size, val);
+		exynos_pcie_prog_viewport_mem_outbound(pp);
+	} else {
+		exynos_pcie_prog_viewport_cfg1(pp, busdev);
+		ret = cfg_read(pp->va_cfg1_base + address, where, size, val);
+		exynos_pcie_prog_viewport_io_outbound(pp);
+	}
+
+	return ret;
+}
+
+static int exynos_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+		u32 devfn, int where, int size, u32 val)
+{
+	int ret = PCIBIOS_SUCCESSFUL;
+	u32 address, busdev;
+
+	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
+		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
+	address = where & ~0x3;
+
+	if (bus->parent->number == pp->root_bus_nr) {
+		exynos_pcie_prog_viewport_cfg0(pp, busdev);
+		ret = cfg_write(pp->va_cfg0_base + address, where, size, val);
+		exynos_pcie_prog_viewport_mem_outbound(pp);
+	} else {
+		exynos_pcie_prog_viewport_cfg1(pp, busdev);
+		ret = cfg_write(pp->va_cfg1_base + address, where, size, val);
+		exynos_pcie_prog_viewport_io_outbound(pp);
+	}
+
+	return ret;
+}
+
+static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
+{
+	struct pcie_port *pp;
+
+	pp = sys_to_pcie(sys);
+
+	if (!pp)
+		return 0;
+
+	pci_add_resource(&sys->resources, &pp->io);
+	pci_add_resource(&sys->resources, &pp->mem);
+
+	return 1;
+}
+
+static int exynos_pcie_link_up(struct pcie_port *pp)
+{
+	u32 val = readl(pp->elbi_base + PCIE_ELBI_RDLH_LINKUP);
+	if (val == PCIE_ELBI_LTSSM_ENABLE)
+		return 1;
+
+	return 0;
+}
+
+static int exynos_pcie_valid_config(struct pcie_port *pp,
+				struct pci_bus *bus, int dev)
+{
+	/* If there is no link, then there is no device */
+	if (bus->number != pp->root_bus_nr) {
+		if (!exynos_pcie_link_up(pp))
+			return 0;
+	}
+
+	/* access only one slot on each root port */
+	if (bus->number == pp->root_bus_nr && dev > 0)
+		return 0;
+
+	/*
+	 * do not read more than one device on the bus directly attached
+	 * to RC's (Virtual Bridge's) DS side.
+	 */
+	if (bus->primary == pp->root_bus_nr && dev > 0)
+		return 0;
+
+	return 1;
+}
+
+static int exynos_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
+			int size, u32 *val)
+{
+	struct pcie_port *pp = sys_to_pcie(bus->sysdata);
+	unsigned long flags;
+	int ret;
+
+	if (!pp) {
+		BUG();
+		return -EINVAL;
+	}
+
+	if (exynos_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0) {
+		*val = 0xffffffff;
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	spin_lock_irqsave(&pp->conf_lock, flags);
+	if (bus->number != pp->root_bus_nr)
+		ret = exynos_pcie_rd_other_conf(pp, bus, devfn,
+						where, size, val);
+	else
+		ret = exynos_pcie_rd_own_conf(pp, where, size, val);
+	spin_unlock_irqrestore(&pp->conf_lock, flags);
+
+	return ret;
+}
+
+static int exynos_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
+			int where, int size, u32 val)
+{
+	struct pcie_port *pp = sys_to_pcie(bus->sysdata);
+	unsigned long flags;
+	int ret;
+
+	if (!pp) {
+		BUG();
+		return -EINVAL;
+	}
+
+	if (exynos_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	spin_lock_irqsave(&pp->conf_lock, flags);
+	if (bus->number != pp->root_bus_nr)
+		ret = exynos_pcie_wr_other_conf(pp, bus, devfn,
+						where, size, val);
+	else
+		ret = exynos_pcie_wr_own_conf(pp, where, size, val);
+	spin_unlock_irqrestore(&pp->conf_lock, flags);
+
+	return ret;
+}
+
+static struct pci_ops exynos_pcie_ops = {
+	.read = exynos_pcie_rd_conf,
+	.write = exynos_pcie_wr_conf,
+};
+
+static struct pci_bus *exynos_pcie_scan_bus(int nr,
+					struct pci_sys_data *sys)
+{
+	struct pci_bus *bus;
+	struct pcie_port *pp = sys_to_pcie(sys);
+
+	if (pp) {
+		pp->root_bus_nr = sys->busnr;
+		bus = pci_scan_root_bus(NULL, sys->busnr, &exynos_pcie_ops,
+					sys, &sys->resources);
+		return bus;
+	} else {
+		bus = NULL;
+		BUG();
+	}
+
+	return bus;
+}
+
+static int exynos_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
+
+	return pp->irq;
+}
+
+static struct hw_pci exynos_pci = {
+	.setup		= exynos_pcie_setup,
+	.scan		= exynos_pcie_scan_bus,
+	.map_irq	= exynos_pcie_map_irq,
+};
+
+static void exynos_pcie_setup_rc(struct pcie_port *pp)
+{
+	struct pcie_port_info *config = &pp->config;
+	void __iomem *dbi_base = pp->dbi_base;
+	u32 val;
+	u32 membase;
+	u32 memlimit;
+
+	/* set the number of lines as 4 */
+	readl_rc(pp, dbi_base + PCIE_PORT_LINK_CONTROL, &val);
+	val &= ~PORT_LINK_MODE_MASK;
+	val |= PORT_LINK_MODE_4_LANES;
+	writel_rc(pp, val, dbi_base + PCIE_PORT_LINK_CONTROL);
+
+	/* set link width speed control register */
+	readl_rc(pp, dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL, &val);
+	val &= ~PORT_LOGIC_LINK_WIDTH_MASK;
+	val |= PORT_LOGIC_LINK_WIDTH_4_LANES;
+	writel_rc(pp, val, dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+
+	/* setup RC BARs */
+	writel_rc(pp, 0x00000004, dbi_base + PCI_BASE_ADDRESS_0);
+	writel_rc(pp, 0x00000004, dbi_base + PCI_BASE_ADDRESS_1);
+
+	/* setup interrupt pins */
+	readl_rc(pp, dbi_base + PCI_INTERRUPT_LINE, &val);
+	val &= 0xffff00ff;
+	val |= 0x00000100;
+	writel_rc(pp, val, dbi_base + PCI_INTERRUPT_LINE);
+
+	/* setup bus numbers */
+	readl_rc(pp, dbi_base + PCI_PRIMARY_BUS, &val);
+	val &= 0xff000000;
+	val |= 0x00010100;
+	writel_rc(pp, val, dbi_base + PCI_PRIMARY_BUS);
+
+	/* setup memory base, memory limit */
+	membase = ((u32)pp->mem_base & 0xfff00000) >> 16;
+	memlimit = (config->mem_size + (u32)pp->mem_base) & 0xfff00000;
+	val = memlimit | membase;
+	writel_rc(pp, val, dbi_base + PCI_MEMORY_BASE);
+
+	/* setup command register */
+	readl_rc(pp, dbi_base + PCI_COMMAND, &val);
+	val &= 0xffff0000;
+	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
+		PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
+	writel_rc(pp, val, dbi_base + PCI_COMMAND);
+}
+
+static void exynos_pcie_assert_core_reset(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+
+	val = readl(elbi_base + PCIE_CORE_RESET);
+	val &= ~PCIE_CORE_RESET_ENABLE;
+	writel(val, elbi_base + PCIE_CORE_RESET);
+	writel(0, elbi_base + PCIE_PWR_RESET);
+	writel(0, elbi_base + PCIE_STICKY_RESET);
+	writel(0, elbi_base + PCIE_NONSTICKY_RESET);
+}
+
+static void exynos_pcie_deassert_core_reset(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+	void __iomem *purple_base = pp->purple_base;
+
+	val = readl(elbi_base + PCIE_CORE_RESET);
+	val |= PCIE_CORE_RESET_ENABLE;
+	writel(val, elbi_base + PCIE_CORE_RESET);
+	writel(1, elbi_base + PCIE_STICKY_RESET);
+	writel(1, elbi_base + PCIE_NONSTICKY_RESET);
+	writel(1, elbi_base + PCIE_APP_INIT_RESET);
+	writel(0, elbi_base + PCIE_APP_INIT_RESET);
+	writel(1, purple_base + PCIE_PHY_MAC_RESET);
+}
+
+static void exynos_pcie_assert_phy_reset(struct pcie_port *pp)
+{
+	void __iomem *purple_base = pp->purple_base;
+
+	writel(0, purple_base + PCIE_PHY_MAC_RESET);
+	writel(1, purple_base + PCIE_PHY_GLOBAL_RESET);
+}
+
+static void exynos_pcie_deassert_phy_reset(struct pcie_port *pp)
+{
+	void __iomem *elbi_base = pp->elbi_base;
+	void __iomem *purple_base = pp->purple_base;
+
+	writel(0, purple_base + PCIE_PHY_GLOBAL_RESET);
+	writel(1, elbi_base + PCIE_PWR_RESET);
+	writel(0, purple_base + PCIE_PHY_COMMON_RESET);
+	writel(0, purple_base + PCIE_PHY_CMN_REG);
+	writel(0, purple_base + PCIE_PHY_TRSVREG_RESET);
+	writel(0, purple_base + PCIE_PHY_TRSV_RESET);
+}
+
+static void exynos_pcie_init_phy(struct pcie_port *pp)
+{
+	void __iomem *phy_base = pp->phy_base;
+
+	/* DCC feedback control off */
+	writel(0x29, phy_base + PCIE_PHY_DCC_FEEDBACK);
+
+	/* set TX/RX impedance */
+	writel(0xd5, phy_base + PCIE_PHY_IMPEDANCE);
+
+	/* set 50Mhz PHY clock */
+	writel(0x14, phy_base + PCIE_PHY_PLL_DIV_0);
+	writel(0x12, phy_base + PCIE_PHY_PLL_DIV_1);
+
+	/* set TX Differential output for lane 0 */
+	writel(0x7f, phy_base + PCIE_PHY_TRSV0_DRV_LVL);
+
+	/* set TX Pre-emphasis Level Control for lane 0 to minimum */
+	writel(0x0, phy_base + PCIE_PHY_TRSV0_EMP_LVL);
+
+	/* set RX clock and data recovery bandwidth */
+	writel(0xe7, phy_base + PCIE_PHY_PLL_BIAS);
+	writel(0x82, phy_base + PCIE_PHY_TRSV0_RXCDR);
+	writel(0x82, phy_base + PCIE_PHY_TRSV1_RXCDR);
+	writel(0x82, phy_base + PCIE_PHY_TRSV2_RXCDR);
+	writel(0x82, phy_base + PCIE_PHY_TRSV3_RXCDR);
+
+	/* change TX Pre-emphasis Level Control for lanes */
+	writel(0x39, phy_base + PCIE_PHY_TRSV0_EMP_LVL);
+	writel(0x39, phy_base + PCIE_PHY_TRSV1_EMP_LVL);
+	writel(0x39, phy_base + PCIE_PHY_TRSV2_EMP_LVL);
+	writel(0x39, phy_base + PCIE_PHY_TRSV3_EMP_LVL);
+
+	/* set LVCC */
+	writel(0x20, phy_base + PCIE_PHY_TRSV0_LVCC);
+	writel(0xa0, phy_base + PCIE_PHY_TRSV1_LVCC);
+	writel(0xa0, phy_base + PCIE_PHY_TRSV2_LVCC);
+	writel(0xa0, phy_base + PCIE_PHY_TRSV3_LVCC);
+}
+
+static void exynos_pcie_assert_reset(struct pcie_port *pp)
+{
+	if (pp->reset_gpio >= 0)
+		devm_gpio_request_one(pp->dev, pp->reset_gpio,
+				GPIOF_OUT_INIT_HIGH, "RESET");
+	return;
+}
+
+static int exynos_pcie_establish_link(struct pcie_port *pp)
+{
+	u32 val;
+	int count = 0;
+	void __iomem *elbi_base = pp->elbi_base;
+	void __iomem *purple_base = pp->purple_base;
+	void __iomem *phy_base = pp->phy_base;
+
+	if (exynos_pcie_link_up(pp)) {
+		dev_err(pp->dev, "Link already up\n");
+		return 0;
+	}
+
+	/* assert reset signals */
+	exynos_pcie_assert_core_reset(pp);
+	exynos_pcie_assert_phy_reset(pp);
+
+	/* de-assert phy reset */
+	exynos_pcie_deassert_phy_reset(pp);
+
+	/* initialize phy */
+	exynos_pcie_init_phy(pp);
+
+	/* pulse for common reset */
+	writel(1, purple_base + PCIE_PHY_COMMON_RESET);
+	udelay(500);
+	writel(0, purple_base + PCIE_PHY_COMMON_RESET);
+
+	/* de-assert core reset */
+	exynos_pcie_deassert_core_reset(pp);
+
+	/* setup root complex */
+	exynos_pcie_setup_rc(pp);
+
+	/* assert reset signal */
+	exynos_pcie_assert_reset(pp);
+
+	/* assert LTSSM enable */
+	writel(PCIE_ELBI_LTSSM_ENABLE, elbi_base + PCIE_APP_LTSSM_ENABLE);
+
+	/* check if the link is up or not */
+	while (!exynos_pcie_link_up(pp)) {
+		mdelay(100);
+		count++;
+		if (count == 10) {
+			while (readl(phy_base + PCIE_PHY_PLL_LOCKED) == 0) {
+				val = readl(purple_base + PCIE_PHY_PLL_LOCKED);
+				dev_info(pp->dev, "PLL Locked: 0x%x\n", val);
+			}
+			dev_err(pp->dev, "PCIe Link Fail\n");
+			return -EINVAL;
+		}
+	}
+
+	dev_info(pp->dev, "Link up\n");
+
+	return 0;
+}
+
+static void exynos_pcie_clear_irq_pulse(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+
+	val = readl(elbi_base + PCIE_IRQ_PULSE);
+	writel(val, elbi_base + PCIE_IRQ_PULSE);
+	return;
+}
+
+static void exynos_pcie_enable_irq_pulse(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+
+	/* enable INTX interrupt */
+	val = IRQ_INTA_ASSERT | IRQ_INTB_ASSERT |
+		IRQ_INTC_ASSERT | IRQ_INTD_ASSERT,
+	writel(val, elbi_base + PCIE_IRQ_EN_PULSE);
+	return;
+}
+
+static irqreturn_t exynos_pcie_irq_handler(int irq, void *arg)
+{
+	struct pcie_port *pp = arg;
+
+	exynos_pcie_clear_irq_pulse(pp);
+	return IRQ_HANDLED;
+}
+
+static void exynos_pcie_enable_interrupts(struct pcie_port *pp)
+{
+	exynos_pcie_enable_irq_pulse(pp);
+	return;
+}
+
+static void exynos_pcie_host_init(struct pcie_port *pp)
+{
+	struct pcie_port_info *config = &pp->config;
+	u32 val;
+
+	/* Keep first 64K for IO */
+	pp->cfg0_base = pp->cfg.start;
+	pp->cfg1_base = pp->cfg.start + config->cfg0_size;
+	pp->io_base = pp->io.start;
+	pp->mem_base = pp->mem.start;
+
+	/* enable link */
+	exynos_pcie_establish_link(pp);
+
+	/* set view ports for inbound */
+	exynos_pcie_prog_viewport_mem_inbound(pp);
+	exynos_pcie_prog_viewport_io_inbound(pp);
+
+	exynos_pcie_wr_own_conf(pp, PCI_BASE_ADDRESS_0, 4, 0);
+
+	/* program correct class for RC */
+	exynos_pcie_wr_own_conf(pp, PCI_CLASS_DEVICE, 2, PCI_CLASS_BRIDGE_PCI);
+
+	exynos_pcie_rd_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, &val);
+	val |= PORT_LOGIC_SPEED_CHANGE;
+	exynos_pcie_wr_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, val);
+
+	exynos_pcie_enable_interrupts(pp);
+}
+
+static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev)
+{
+	struct resource *elbi_base;
+	struct resource *phy_base;
+	struct resource *purple_base;
+	int ret;
+
+	elbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!elbi_base) {
+		dev_err(&pdev->dev, "couldn't get elbi base resource\n");
+		return -EINVAL;
+	}
+	pp->elbi_base = devm_ioremap_resource(&pdev->dev, elbi_base);
+	if (IS_ERR(pp->elbi_base))
+		return PTR_ERR(pp->elbi_base);
+
+	phy_base = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!phy_base) {
+		dev_err(&pdev->dev, "couldn't get phy base resource\n");
+		return -EINVAL;
+	}
+	pp->phy_base = devm_ioremap_resource(&pdev->dev, phy_base);
+	if (IS_ERR(pp->phy_base))
+		return PTR_ERR(pp->phy_base);
+
+	purple_base = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (!purple_base) {
+		dev_err(&pdev->dev, "couldn't get purple base resource\n");
+		return -EINVAL;
+	}
+	pp->purple_base = devm_ioremap_resource(&pdev->dev, purple_base);
+	if (IS_ERR(pp->purple_base))
+		return PTR_ERR(pp->purple_base);
+
+	pp->irq = platform_get_irq(pdev, 1);
+	if (!pp->irq) {
+		dev_err(&pdev->dev, "failed to get irq\n");
+		return -ENODEV;
+	}
+	ret = devm_request_irq(&pdev->dev, pp->irq, exynos_pcie_irq_handler,
+				IRQF_SHARED, "exynos-pcie", pp);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request irq\n");
+		return ret;
+	}
+
+	pp->dbi_base = devm_ioremap(&pdev->dev, pp->cfg.start,
+				resource_size(&pp->cfg));
+	if (!pp->dbi_base) {
+		dev_err(&pdev->dev, "error with ioremap\n");
+		return -ENOMEM;
+	}
+
+	pp->root_bus_nr = -1;
+
+	spin_lock_init(&pp->conf_lock);
+	exynos_pcie_host_init(pp);
+	pp->va_cfg0_base = devm_ioremap(&pdev->dev, pp->cfg0_base,
+					pp->config.cfg0_size);
+	if (!pp->va_cfg0_base) {
+		dev_err(pp->dev, "error with ioremap in function\n");
+		return -ENOMEM;
+	}
+	pp->va_cfg1_base = devm_ioremap(&pdev->dev, pp->cfg1_base,
+					pp->config.cfg1_size);
+	if (!pp->va_cfg1_base) {
+		dev_err(pp->dev, "error with ioremap\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int __init exynos_pcie_probe(struct platform_device *pdev)
+{
+	struct pcie_port *pp;
+	struct device_node *np = pdev->dev.of_node;
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	int ret;
+
+	pp = devm_kzalloc(&pdev->dev, sizeof(*pp), GFP_KERNEL);
+	if (!pp) {
+		dev_err(&pdev->dev, "no memory for pcie port\n");
+		return -ENOMEM;
+	}
+
+	pp->dev = &pdev->dev;
+
+	if (of_pci_range_parser_init(&parser, np)) {
+		dev_err(&pdev->dev, "missing ranges property\n");
+		return -EINVAL;
+	}
+
+	/* Get the I/O and memory ranges from DT */
+	for_each_of_pci_range(&parser, &range) {
+		unsigned long restype = range.flags & IORESOURCE_TYPE_BITS;
+		if (restype == IORESOURCE_IO) {
+			of_pci_range_to_resource(&range, np, &pp->io);
+			pp->io.name = "I/O";
+			pp->config.io_size = resource_size(&pp->io);
+			pp->config.io_bus_addr = range.pci_addr;
+		}
+		if (restype == IORESOURCE_MEM) {
+			of_pci_range_to_resource(&range, np, &pp->mem);
+			pp->mem.name = "MEM";
+			pp->config.mem_size = resource_size(&pp->mem);
+			pp->config.mem_bus_addr = range.pci_addr;
+		}
+		if (restype == 0) {
+			of_pci_range_to_resource(&range, np, &pp->cfg);
+			pp->config.cfg0_size = resource_size(&pp->cfg)/2;
+			pp->config.cfg1_size = resource_size(&pp->cfg)/2;
+		}
+	}
+
+	pp->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+
+	pp->clk = devm_clk_get(&pdev->dev, "pcie");
+	if (IS_ERR(pp->clk)) {
+		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
+		return PTR_ERR(pp->clk);
+	}
+	ret = clk_prepare_enable(pp->clk);
+	if (ret)
+		return ret;
+
+	pp->bus_clk = devm_clk_get(&pdev->dev, "pcie_bus");
+	if (IS_ERR(pp->bus_clk)) {
+		dev_err(&pdev->dev, "Failed to get pcie bus clock\n");
+		ret = PTR_ERR(pp->bus_clk);
+		goto fail_clk;
+	}
+	ret = clk_prepare_enable(pp->bus_clk);
+	if (ret)
+		goto fail_clk;
+
+	ret = add_pcie_port(pp, pdev);
+	if (ret < 0)
+		goto fail_bus_clk;
+
+	pp->controller = exynos_pci.nr_controllers;
+	exynos_pci.nr_controllers = 1;
+	exynos_pci.private_data = (void **)&pp;
+
+	pci_common_init(&exynos_pci);
+	pci_assign_unassigned_resources();
+#ifdef CONFIG_PCI_DOMAINS
+	exynos_pci.domain++;
+#endif
+
+	platform_set_drvdata(pdev, pp);
+	return 0;
+
+fail_bus_clk:
+	clk_disable_unprepare(pp->bus_clk);
+fail_clk:
+	clk_disable_unprepare(pp->clk);
+	return ret;
+}
+
+static int __exit exynos_pcie_remove(struct platform_device *pdev)
+{
+	struct pcie_port *pp = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(pp->bus_clk);
+	clk_disable_unprepare(pp->clk);
+
+	return 0;
+}
+
+static const struct of_device_id exynos_pcie_of_match[] = {
+	{ .compatible = "samsung,exynos5440-pcie", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, exynos_pcie_of_match);
+
+static struct platform_driver exynos_pcie_driver = {
+	.remove		= __exit_p(exynos_pcie_remove),
+	.driver = {
+		.name	= "exynos-pcie",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(exynos_pcie_of_match),
+	},
+};
+
+static int exynos_pcie_abort(unsigned long addr, unsigned int fsr,
+			struct pt_regs *regs)
+{
+	unsigned long pc = instruction_pointer(regs);
+	unsigned long instr = *(unsigned long *)pc;
+
+	WARN_ONCE(1, "pcie abort\n");
+
+	/*
+	 * If the instruction being executed was a read,
+	 * make it look like it read all-ones.
+	 */
+	if ((instr & 0x0c100000) == 0x04100000) {
+		int reg = (instr >> 12) & 15;
+		unsigned long val;
+
+		if (instr & 0x00400000)
+			val = 255;
+		else
+			val = -1;
+
+		regs->uregs[reg] = val;
+		regs->ARM_pc += 4;
+		return 0;
+	}
+
+	if ((instr & 0x0e100090) == 0x00100090) {
+		int reg = (instr >> 12) & 15;
+
+		regs->uregs[reg] = -1;
+		regs->ARM_pc += 4;
+		return 0;
+	}
+
+	return 1;
+}
+
+static int __init pcie_init(void)
+{
+	hook_fault_code(16 + 6, exynos_pcie_abort, SIGBUS, 0,
+			"imprecise external abort");
+
+	platform_driver_probe(&exynos_pcie_driver, exynos_pcie_probe);
+
+	return 0;
+}
+subsys_initcall(pcie_init);
+
+static void __exit pcie_exit(void)
+{
+	platform_driver_unregister(&exynos_pcie_driver);
+}
+module_exit(pcie_exit);
+
+MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
+MODULE_DESCRIPTION("Samsung PCIe host controller driver");
+MODULE_LICENSE("GPLv2");