diff mbox

[v3,2/2] PCI: mvebu - Support a bridge with no IO port window

Message ID 1383262380-6984-2-git-send-email-jgunthorpe@obsidianresearch.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Jason Gunthorpe Oct. 31, 2013, 11:33 p.m. UTC
Make pcie-io-aperture and the IO port MBUS ID in ranges optional.
If not provided the bridge reports to Linux that IO space mapping is
not supported and refuses to configure an IO mbus window.

This allows both complete disable (do not specify pcie-io-aperture) and
per-port disable (do not specify a IO target ranges entry for the port)

Most PCIE devices these days do not require IO support to function,
so having an option to disable it in the driver is useful.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
---
 drivers/pci/host/pci-mvebu.c | 63 ++++++++++++++++++++++++++++++--------------
 1 file changed, 43 insertions(+), 20 deletions(-)

v3 changes:
 - Remove the bogus <= changes when checking the IO limit register
 - Rebase ontop of 'PCI: mvebu - The bridge should obey the MEM and IO command bits'
   which is a necessary dependency.

Comments

Thomas Petazzoni Nov. 25, 2013, 5:10 p.m. UTC | #1
Dear Jason Gunthorpe,

On Thu, 31 Oct 2013 17:33:00 -0600, Jason Gunthorpe wrote:
> Make pcie-io-aperture and the IO port MBUS ID in ranges optional.
> If not provided the bridge reports to Linux that IO space mapping is
> not supported and refuses to configure an IO mbus window.
> 
> This allows both complete disable (do not specify pcie-io-aperture) and
> per-port disable (do not specify a IO target ranges entry for the port)
> 
> Most PCIE devices these days do not require IO support to function,
> so having an option to disable it in the driver is useful.
> 
> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> ---
>  drivers/pci/host/pci-mvebu.c | 63 ++++++++++++++++++++++++++++++--------------
>  1 file changed, 43 insertions(+), 20 deletions(-)

Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

Thanks, and sorry again for the huge time it took me to test this
version of your patches.

Best regards,

Thomas
Jason Gunthorpe Nov. 26, 2013, 6:06 p.m. UTC | #2
On Mon, Nov 25, 2013 at 06:10:08PM +0100, Thomas Petazzoni wrote:

> Thanks, and sorry again for the huge time it took me to test this
> version of your patches.

Thanks Thomas, I've rebased to v3.13-rc1, re-tested here, and re-sent
the patches.

There are two more you should look at - one should head into v3.13 as
it fixes a small regression.

Bjorn, Jason C has asked these go through your tree from now on.

Thanks,
Jason
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Jason Cooper Nov. 26, 2013, 6:10 p.m. UTC | #3
On Tue, Nov 26, 2013 at 11:06:59AM -0700, Jason Gunthorpe wrote:
> Bjorn, Jason C has asked these go through your tree from now on.

Just to be clear, I don't mind taking patches.  It's just the proper way
is through the maintainer of the affected directory.  Unless other
arrangements have been made.

thx,

Jason.
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diff mbox

Patch

diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index 721fca9..b36b91b 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -132,6 +132,11 @@  struct mvebu_pcie_port {
 	size_t iowin_size;
 };
 
+static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
+{
+	return port->io_target != -1 && port->io_attr != -1;
+}
+
 static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
 {
 	return !(readl(port->base + PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
@@ -293,6 +298,12 @@  static void mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
 		return;
 	}
 
+	if (!mvebu_has_ioport(port)) {
+		dev_WARN(&port->pcie->pdev->dev,
+			 "Attempt to set IO when IO is disabled\n");
+		return;
+	}
+
 	/*
 	 * We read the PCI-to-PCI bridge emulated registers, and
 	 * calculate the base address and size of the address decoding
@@ -407,9 +418,12 @@  static int mvebu_sw_pci_bridge_read(struct mvebu_pcie_port *port,
 		break;
 
 	case PCI_IO_BASE:
-		*value = (bridge->secondary_status << 16 |
-			  bridge->iolimit          <<  8 |
-			  bridge->iobase);
+		if (!mvebu_has_ioport(port))
+			*value = bridge->secondary_status << 16;
+		else
+			*value = (bridge->secondary_status << 16 |
+				  bridge->iolimit          <<  8 |
+				  bridge->iobase);
 		break;
 
 	case PCI_MEMORY_BASE:
@@ -469,6 +483,9 @@  static int mvebu_sw_pci_bridge_write(struct mvebu_pcie_port *port,
 	{
 		u32 old = bridge->command;
 
+		if (!mvebu_has_ioport(port))
+			value &= ~PCI_COMMAND_IO;
+
 		bridge->command = value & 0xffff;
 		if ((old ^ bridge->command) & PCI_COMMAND_IO)
 			mvebu_pcie_handle_iobase_change(port);
@@ -639,7 +656,9 @@  static int __init mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
 	struct mvebu_pcie *pcie = sys_to_pcie(sys);
 	int i;
 
-	pci_add_resource_offset(&sys->resources, &pcie->realio, sys->io_offset);
+	if (resource_size(&pcie->realio) != 0)
+		pci_add_resource_offset(&sys->resources, &pcie->realio,
+					sys->io_offset);
 	pci_add_resource_offset(&sys->resources, &pcie->mem, sys->mem_offset);
 	pci_add_resource(&sys->resources, &pcie->busn);
 
@@ -748,12 +767,17 @@  mvebu_pcie_map_registers(struct platform_device *pdev,
 #define DT_CPUADDR_TO_ATTR(cpuaddr)   (((cpuaddr) >> 48) & 0xFF)
 
 static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
-			      unsigned long type, int *tgt, int *attr)
+			      unsigned long type,
+			      unsigned int *tgt,
+			      unsigned int *attr)
 {
 	const int na = 3, ns = 2;
 	const __be32 *range;
 	int rlen, nranges, rangesz, pna, i;
 
+	*tgt = -1;
+	*attr = -1;
+
 	range = of_get_property(np, "ranges", &rlen);
 	if (!range)
 		return -EINVAL;
@@ -807,16 +831,15 @@  static int __init mvebu_pcie_probe(struct platform_device *pdev)
 	}
 
 	mvebu_mbus_get_pcie_io_aperture(&pcie->io);
-	if (resource_size(&pcie->io) == 0) {
-		dev_err(&pdev->dev, "invalid I/O aperture size\n");
-		return -EINVAL;
-	}
 
-	pcie->realio.flags = pcie->io.flags;
-	pcie->realio.start = PCIBIOS_MIN_IO;
-	pcie->realio.end = min_t(resource_size_t,
-				  IO_SPACE_LIMIT,
-				  resource_size(&pcie->io));
+	if (resource_size(&pcie->io) != 0) {
+		pcie->realio.flags = pcie->io.flags;
+		pcie->realio.start = PCIBIOS_MIN_IO;
+		pcie->realio.end = min_t(resource_size_t,
+					 IO_SPACE_LIMIT,
+					 resource_size(&pcie->io));
+	} else
+		pcie->realio = pcie->io;
 
 	/* Get the bus range */
 	ret = of_pci_parse_bus_range(np, &pcie->busn);
@@ -873,12 +896,12 @@  static int __init mvebu_pcie_probe(struct platform_device *pdev)
 			continue;
 		}
 
-		ret = mvebu_get_tgt_attr(np, port->devfn, IORESOURCE_IO,
-					 &port->io_target, &port->io_attr);
-		if (ret < 0) {
-			dev_err(&pdev->dev, "PCIe%d.%d: cannot get tgt/attr for io window\n",
-				port->port, port->lane);
-			continue;
+		if (resource_size(&pcie->io) != 0)
+			mvebu_get_tgt_attr(np, port->devfn, IORESOURCE_IO,
+					   &port->io_target, &port->io_attr);
+		else {
+			port->io_target = -1;
+			port->io_attr = -1;
 		}
 
 		port->base = mvebu_pcie_map_registers(pdev, child, port);