[v3,5/6] iommu/mediatek: Add mt8173 IOMMU driver
diff mbox

Message ID 1437037475-9065-6-git-send-email-yong.wu@mediatek.com
State New
Headers show

Commit Message

Yong Wu July 16, 2015, 9:04 a.m. UTC
This patch adds support for mediatek m4u (MultiMedia Memory Management
Unit).

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
 drivers/iommu/Kconfig     |   13 +
 drivers/iommu/Makefile    |    1 +
 drivers/iommu/mtk_iommu.c |  724 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 738 insertions(+)
 create mode 100644 drivers/iommu/mtk_iommu.c

Comments

Will Deacon July 21, 2015, 2:59 p.m. UTC | #1
Hi Yong Wu,

On Thu, Jul 16, 2015 at 10:04:34AM +0100, Yong Wu wrote:
> This patch adds support for mediatek m4u (MultiMedia Memory Management
> Unit).

[...]

> +static void mtk_iommu_tlb_flush_all(void *cookie)
> +{
> +       struct mtk_iommu_domain *domain = cookie;
> +       void __iomem *base;
> +
> +       base = domain->data->base;
> +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> +       writel(F_ALL_INVLD, base + REG_MMU_INVALIDATE);

This needs to be synchronous, so you probably want to call
mtk_iommu_tlb_sync at the end.

> +}
> +
> +static void mtk_iommu_tlb_add_flush(unsigned long iova, size_t size,
> +                                   bool leaf, void *cookie)
> +{
> +       struct mtk_iommu_domain *domain = cookie;
> +       void __iomem *base = domain->data->base;
> +       unsigned int iova_start = iova, iova_end = iova + size - 1;
> +
> +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> +
> +       writel(iova_start, base + REG_MMU_INVLD_START_A);
> +       writel(iova_end, base + REG_MMU_INVLD_END_A);
> +       writel(F_MMU_INV_RANGE, base + REG_MMU_INVALIDATE);

Why are you using writel instead of writel_relaxed? I asked this before
but I don't think you replied.

Will
Yong Wu July 24, 2015, 5:43 a.m. UTC | #2
On Tue, 2015-07-21 at 15:59 +0100, Will Deacon wrote:
> Hi Yong Wu,
> 
> On Thu, Jul 16, 2015 at 10:04:34AM +0100, Yong Wu wrote:
> > This patch adds support for mediatek m4u (MultiMedia Memory Management
> > Unit).
> 
> [...]
> 
> > +static void mtk_iommu_tlb_flush_all(void *cookie)
> > +{
> > +       struct mtk_iommu_domain *domain = cookie;
> > +       void __iomem *base;
> > +
> > +       base = domain->data->base;
> > +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> > +       writel(F_ALL_INVLD, base + REG_MMU_INVALIDATE);
> 
> This needs to be synchronous, so you probably want to call
> mtk_iommu_tlb_sync at the end.

From our spec, we have to wait until HW done after tlb flush range.
But it don't need wait after tlb flush all.
so It isn't necessary to add mtk_iommu_tlb_sync in tlb_flush_all here.

> 
> > +}
> > +
> > +static void mtk_iommu_tlb_add_flush(unsigned long iova, size_t size,
> > +                                   bool leaf, void *cookie)
> > +{
> > +       struct mtk_iommu_domain *domain = cookie;
> > +       void __iomem *base = domain->data->base;
> > +       unsigned int iova_start = iova, iova_end = iova + size - 1;
> > +
> > +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> > +
> > +       writel(iova_start, base + REG_MMU_INVLD_START_A);
> > +       writel(iova_end, base + REG_MMU_INVLD_END_A);
> > +       writel(F_MMU_INV_RANGE, base + REG_MMU_INVALIDATE);
> 
> Why are you using writel instead of writel_relaxed? I asked this before
> but I don't think you replied.

Sorry, I didn't notice _relax last time. I will improve in next version.
Thanks very much.

> 
> Will
Will Deacon July 24, 2015, 4:55 p.m. UTC | #3
On Fri, Jul 24, 2015 at 06:43:13AM +0100, Yong Wu wrote:
> On Tue, 2015-07-21 at 15:59 +0100, Will Deacon wrote:
> > On Thu, Jul 16, 2015 at 10:04:34AM +0100, Yong Wu wrote:
> > > +static void mtk_iommu_tlb_flush_all(void *cookie)
> > > +{
> > > +       struct mtk_iommu_domain *domain = cookie;
> > > +       void __iomem *base;
> > > +
> > > +       base = domain->data->base;
> > > +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> > > +       writel(F_ALL_INVLD, base + REG_MMU_INVALIDATE);
> > 
> > This needs to be synchronous, so you probably want to call
> > mtk_iommu_tlb_sync at the end.
> 
> From our spec, we have to wait until HW done after tlb flush range.
> But it don't need wait after tlb flush all.
> so It isn't necessary to add mtk_iommu_tlb_sync in tlb_flush_all here.

Okey doke, but I'm surprised you don't need a subsequent DSB or read-back.
What if the writel is buffered on the way to the IOMMU?

Will
Yong Wu July 27, 2015, 4:24 a.m. UTC | #4
On Fri, 2015-07-24 at 17:55 +0100, Will Deacon wrote:
> On Fri, Jul 24, 2015 at 06:43:13AM +0100, Yong Wu wrote:
> > On Tue, 2015-07-21 at 15:59 +0100, Will Deacon wrote:
> > > On Thu, Jul 16, 2015 at 10:04:34AM +0100, Yong Wu wrote:
> > > > +static void mtk_iommu_tlb_flush_all(void *cookie)
> > > > +{
> > > > +       struct mtk_iommu_domain *domain = cookie;
> > > > +       void __iomem *base;
> > > > +
> > > > +       base = domain->data->base;
> > > > +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> > > > +       writel(F_ALL_INVLD, base + REG_MMU_INVALIDATE);
> > > 
> > > This needs to be synchronous, so you probably want to call
> > > mtk_iommu_tlb_sync at the end.
> > 
> > From our spec, we have to wait until HW done after tlb flush range.
> > But it don't need wait after tlb flush all.
> > so It isn't necessary to add mtk_iommu_tlb_sync in tlb_flush_all here.
> 
> Okey doke, but I'm surprised you don't need a subsequent DSB or read-back.
> What if the writel is buffered on the way to the IOMMU?

Then I change to this:
 //==========
    writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
    writel_relaxed(F_ALL_INVLD, base + REG_MMU_INVALIDATE);    
    dsb(ishst);
//===========
    dsb or mb(). which one is better here?

> 
> Will
Robin Murphy July 27, 2015, 1:23 p.m. UTC | #5
On 16/07/15 10:04, Yong Wu wrote:
> This patch adds support for mediatek m4u (MultiMedia Memory Management
> Unit).
>
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
[...]
> +static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
> +{
> +       struct mtk_iommu_domain *domain = cookie;
> +       unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
> +
> +       dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
> +                    size, DMA_TO_DEVICE);

Nit: this looks like it may as well be dma_map_single.

It would probably be worth following it with a matching unmap too, just 
to avoid any possible leakage bugs (especially if this M4U ever appears 
in a SoC supporting RAM above the 32-bit boundary).

 > +}
 > +
[...]
> +static int mtk_iommu_parse_dt(struct platform_device *pdev,
> +                             struct mtk_iommu_data *data)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct device_node *ofnode;
> +       struct resource *res;
> +       int i;
> +
> +       ofnode = dev->of_node;
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       data->base = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(data->base))
> +               return PTR_ERR(data->base);
> +
> +       data->irq = platform_get_irq(pdev, 0);
> +       if (data->irq < 0)
> +               return data->irq;
> +
> +       data->bclk = devm_clk_get(dev, "bclk");
> +       if (IS_ERR(data->bclk))
> +               return PTR_ERR(data->bclk);
> +
> +       data->larb_nr = of_count_phandle_with_args(
> +                                       ofnode, "mediatek,larb", NULL);
> +       if (data->larb_nr < 0)
> +               return data->larb_nr;
> +
> +       for (i = 0; i < data->larb_nr; i++) {
> +               struct device_node *larbnode;
> +               struct platform_device *plarbdev;
> +
> +               larbnode = of_parse_phandle(ofnode, "mediatek,larb", i);
> +               if (!larbnode)
> +                       return -EINVAL;
> +
> +               plarbdev = of_find_device_by_node(larbnode);
> +               of_node_put(larbnode);
> +               if (!plarbdev)
> +                       return -EPROBE_DEFER;
> +               data->larbdev[i] = &plarbdev->dev;
> +       }

At a glance this seems like a job for of_parse_phandle_with_args, but I 
may be missing something subtle.

> +       return 0;
> +}
> +
[...]
> +static int mtk_iommu_init_domain_context(struct mtk_iommu_domain *dom)
> +{
> +       int ret;
> +
> +       if (dom->iop)
> +               return 0;
> +
> +       spin_lock_init(&dom->pgtlock);
> +       dom->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS |
> +                       IO_PGTABLE_QUIRK_SHORT_SUPERSECTION |
> +                       IO_PGTABLE_QUIRK_SHORT_MTK;
> +       dom->cfg.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
> +       dom->cfg.ias = 32;
> +       dom->cfg.oas = 32;
> +       dom->cfg.tlb = &mtk_iommu_gather_ops;
> +
> +       dom->iop = alloc_io_pgtable_ops(ARM_SHORT_DESC, &dom->cfg, dom);
> +       if (!dom->iop) {
> +               pr_err("Failed to alloc io pgtable\n");
> +               return -EINVAL;
> +       }
> +
> +       /* Update our support page sizes bitmap */
> +       mtk_iommu_ops.pgsize_bitmap = dom->cfg.pgsize_bitmap;
> +
> +       ret = mtk_iommu_hw_init(dom);
> +       if (ret)
> +               free_io_pgtable_ops(dom->iop);
> +
> +       return ret;
> +}

I don't see that you need the above function at all - since your 
pagetable config is fixed and doesn't have any depency on which IOMMU 
you're attaching to, can't you just do all of that straight away in 
domain_alloc?

> +static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
> +{
> +       struct mtk_iommu_domain *priv;
> +
> +       /* We only support unmanaged domains for now */
> +       if (type != IOMMU_DOMAIN_UNMANAGED)
> +               return NULL;

Have you had a chance to play with the latest DMA mapping series now 
that I've integrated the default domain changes? I think if you handled 
IOMMU_DOMAIN_DMA requests here and made them always return the 
(preallocated) private domain, you should be able to get rid of the 
tricks in attach_device completely.

> +       priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> +       if (!priv)
> +               return NULL;
> +
> +       priv->domain.geometry.aperture_start = 0;
> +       priv->domain.geometry.aperture_end = (1ULL << 32) - 1;

DMA_BIT_MASK(32) ?

> +       priv->domain.geometry.force_aperture = true;
> +
> +       return &priv->domain;
> +}
> +
[...]
> +static int mtk_iommu_add_device(struct device *dev)
> +{
> +       struct mtk_iommu_domain *mtkdom;
> +       struct iommu_group *group;
> +       struct mtk_iommu_client_priv *devhead;
> +       int ret;
> +
> +       if (!dev->archdata.dma_ops)/* Not a iommu client device */
> +               return -ENODEV;

I think archdata.dma_ops is the wrong thing to test here. It would be 
better to use archdata.iommu, since you go on to dereference that 
unconditionally anyway, plus then you only depend on your own of_xlate 
behaviour, rather than some quirk of the arch code (which could quietly 
change in future).

> +       group = iommu_group_get(dev);
> +       if (!group) {
> +               group = iommu_group_alloc();
> +               if (IS_ERR(group)) {
> +                       dev_err(dev, "Failed to allocate IOMMU group\n");
> +                       return PTR_ERR(group);
> +               }
> +       }
> +
> +       ret = iommu_group_add_device(group, dev);
> +       if (ret) {
> +               dev_err(dev, "Failed to add IOMMU group\n");
> +               goto err_group_put;
> +       }
> +
> +       /* get the mtk_iommu_domain from the iommu device */
> +       devhead = dev->archdata.iommu;
> +       mtkdom = devhead->imudev->archdata.iommu;
> +       ret = iommu_attach_group(&mtkdom->domain, group);
> +       if (ret)
> +               dev_err(dev, "Failed to attach IOMMU group\n");
> +
> +err_group_put:
> +       iommu_group_put(group);
> +       return ret;
> +}
> +
[...]
> +static struct iommu_ops mtk_iommu_ops = {
> +       .domain_alloc   = mtk_iommu_domain_alloc,
> +       .domain_free    = mtk_iommu_domain_free,
> +       .attach_dev     = mtk_iommu_attach_device,
> +       .detach_dev     = mtk_iommu_detach_device,
> +       .map            = mtk_iommu_map,
> +       .unmap          = mtk_iommu_unmap,
> +       .map_sg         = default_iommu_map_sg,
> +       .iova_to_phys   = mtk_iommu_iova_to_phys,
> +       .add_device     = mtk_iommu_add_device,
> +       .of_xlate       = mtk_iommu_of_xlate,
> +       .pgsize_bitmap  = -1UL,

As above, if you know the hardware only supports a single descriptor 
format with a fixed set of page sizes, why not just represent that directly?

> +};
> +
[...]
> +static int mtk_iommu_suspend(struct device *dev)
> +{
> +       struct mtk_iommu_domain *mtkdom = dev_get_drvdata(dev);
> +       struct mtk_iommu_data *data = mtkdom->data;
> +       void __iomem *base = data->base;
> +       unsigned int i = 0;
> +
> +       data->reg[i++] = readl(base + REG_MMU_PT_BASE_ADDR);

Redundancy nit: any particular reason for saving this here rather than 
simply restoring it from mtkdom->cfg.arm_short_cfg.ttbr[0] on resume?

> +       data->reg[i++] = readl(base + REG_MMU_STANDARD_AXI_MODE);
> +       data->reg[i++] = readl(base + REG_MMU_DCM_DIS);
> +       data->reg[i++] = readl(base + REG_MMU_CTRL_REG);
> +       data->reg[i++] = readl(base + REG_MMU_IVRP_PADDR);
> +       data->reg[i++] = readl(base + REG_MMU_INT_CONTROL0);
> +       data->reg[i++] = readl(base + REG_MMU_INT_MAIN_CONTROL);

Nit: given that these are fairly arbitrary discontiguous registers so 
you can't have a simple loop over the array, it might be clearer to 
replace the array with an equivalent struct, e.g.:

struct mtk_iommu_suspend_regs {
	u32 standard_axi_mode;
	u32 dcm_dis;
	...
}

	...
	data->reg.dcm_dis = readl(base + REG_MMU_DCM_DIS);
	...

then since you refer to everything by name you don't have to worry about 
the length and order of array elements if anything ever changes.

> +       return 0;
> +}
> +
> +static int mtk_iommu_resume(struct device *dev)
> +{
> +       struct mtk_iommu_domain *mtkdom = dev_get_drvdata(dev);
> +       struct mtk_iommu_data *data = mtkdom->data;
> +       void __iomem *base = data->base;
> +       unsigned int i = 0;
> +
> +       writel(data->reg[i++], base + REG_MMU_PT_BASE_ADDR);
> +       writel(data->reg[i++], base + REG_MMU_STANDARD_AXI_MODE);
> +       writel(data->reg[i++], base + REG_MMU_DCM_DIS);
> +       writel(data->reg[i++], base + REG_MMU_CTRL_REG);
> +       writel(data->reg[i++], base + REG_MMU_IVRP_PADDR);
> +       writel(data->reg[i++], base + REG_MMU_INT_CONTROL0);
> +       writel(data->reg[i++], base + REG_MMU_INT_MAIN_CONTROL);
> +       return 0;
> +}

Other than that though, modulo the issues with the pagetable code I 
think this part of the driver is shaping up quite nicely.

Robin.
Russell King - ARM Linux July 27, 2015, 3:31 p.m. UTC | #6
On Mon, Jul 27, 2015 at 02:23:26PM +0100, Robin Murphy wrote:
> On 16/07/15 10:04, Yong Wu wrote:
> >This patch adds support for mediatek m4u (MultiMedia Memory Management
> >Unit).
> >
> >Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> [...]
> >+static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
> >+{
> >+       struct mtk_iommu_domain *domain = cookie;
> >+       unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
> >+
> >+       dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
> >+                    size, DMA_TO_DEVICE);
> 
> Nit: this looks like it may as well be dma_map_single.
> 
> It would probably be worth following it with a matching unmap too, just to
> avoid any possible leakage bugs (especially if this M4U ever appears in a
> SoC supporting RAM above the 32-bit boundary).

Why not do the job properly?  Take a look at how I implemented the
streaming DMA API on Tegra SMMU (patch set recently sent out earlier
today).

There's no need for hacks like dma_map_page() (and discarding it's
return value) or dma_map_page() followed by dma_unmap_page().
Will Deacon July 27, 2015, 3:48 p.m. UTC | #7
On Mon, Jul 27, 2015 at 05:24:31AM +0100, Yong Wu wrote:
> On Fri, 2015-07-24 at 17:55 +0100, Will Deacon wrote:
> > On Fri, Jul 24, 2015 at 06:43:13AM +0100, Yong Wu wrote:
> > > On Tue, 2015-07-21 at 15:59 +0100, Will Deacon wrote:
> > > > On Thu, Jul 16, 2015 at 10:04:34AM +0100, Yong Wu wrote:
> > > > > +static void mtk_iommu_tlb_flush_all(void *cookie)
> > > > > +{
> > > > > +       struct mtk_iommu_domain *domain = cookie;
> > > > > +       void __iomem *base;
> > > > > +
> > > > > +       base = domain->data->base;
> > > > > +       writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
> > > > > +       writel(F_ALL_INVLD, base + REG_MMU_INVALIDATE);
> > > > 
> > > > This needs to be synchronous, so you probably want to call
> > > > mtk_iommu_tlb_sync at the end.
> > > 
> > > From our spec, we have to wait until HW done after tlb flush range.
> > > But it don't need wait after tlb flush all.
> > > so It isn't necessary to add mtk_iommu_tlb_sync in tlb_flush_all here.
> > 
> > Okey doke, but I'm surprised you don't need a subsequent DSB or read-back.
> > What if the writel is buffered on the way to the IOMMU?
> 
> Then I change to this:
>  //==========
>     writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
>     writel_relaxed(F_ALL_INVLD, base + REG_MMU_INVALIDATE);    
>     dsb(ishst);
> //===========
>     dsb or mb(). which one is better here?

I think you should use mb();

Will
Robin Murphy July 27, 2015, 3:49 p.m. UTC | #8
On 27/07/15 16:31, Russell King - ARM Linux wrote:
> On Mon, Jul 27, 2015 at 02:23:26PM +0100, Robin Murphy wrote:
>> On 16/07/15 10:04, Yong Wu wrote:
>>> This patch adds support for mediatek m4u (MultiMedia Memory Management
>>> Unit).
>>>
>>> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
>> [...]
>>> +static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
>>> +{
>>> +       struct mtk_iommu_domain *domain = cookie;
>>> +       unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
>>> +
>>> +       dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
>>> +                    size, DMA_TO_DEVICE);
>>
>> Nit: this looks like it may as well be dma_map_single.
>>
>> It would probably be worth following it with a matching unmap too, just to
>> avoid any possible leakage bugs (especially if this M4U ever appears in a
>> SoC supporting RAM above the 32-bit boundary).
>
> Why not do the job properly?  Take a look at how I implemented the
> streaming DMA API on Tegra SMMU (patch set recently sent out earlier
> today).
>
> There's no need for hacks like dma_map_page() (and discarding it's
> return value) or dma_map_page() followed by dma_unmap_page().

Indeed, as it happens I do have a branch where I prototyped that for the 
long-descriptor io-pgtable-arm code a while ago; this discussion has 
prompted me to dig it up again. Stay tuned, folks...

Robin.
Yong Wu July 29, 2015, 5:41 a.m. UTC | #9
On Mon, 2015-07-27 at 16:49 +0100, Robin Murphy wrote:
> On 27/07/15 16:31, Russell King - ARM Linux wrote:
> > On Mon, Jul 27, 2015 at 02:23:26PM +0100, Robin Murphy wrote:
> >> On 16/07/15 10:04, Yong Wu wrote:
> >>> This patch adds support for mediatek m4u (MultiMedia Memory Management
> >>> Unit).
> >>>
> >>> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> >> [...]
> >>> +static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
> >>> +{
> >>> +       struct mtk_iommu_domain *domain = cookie;
> >>> +       unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
> >>> +
> >>> +       dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
> >>> +                    size, DMA_TO_DEVICE);
> >>
> >> Nit: this looks like it may as well be dma_map_single.
> >>
> >> It would probably be worth following it with a matching unmap too, just to
> >> avoid any possible leakage bugs (especially if this M4U ever appears in a
> >> SoC supporting RAM above the 32-bit boundary).
> >
> > Why not do the job properly?  Take a look at how I implemented the
> > streaming DMA API on Tegra SMMU (patch set recently sent out earlier
> > today).
> >
> > There's no need for hacks like dma_map_page() (and discarding it's
> > return value) or dma_map_page() followed by dma_unmap_page().
> 
> Indeed, as it happens I do have a branch where I prototyped that for the 
> long-descriptor io-pgtable-arm code a while ago; this discussion has 
> prompted me to dig it up again. Stay tuned, folks...

Hi Russell, Robin,

     From I see in arm-smmu-v3.c in v4.2-rc1, 
     
     The flush_pgtable seems like this:
//==========
	dma_addr_t dma_addr;

	dma_addr = dma_map_page(dev, ptr, size, DMA_TO_DEVICE);

	if (dma_mapping_error(dev, dma_addr))
		dev_err(dev, "failed to flush pgtable at %p\n", ptr);
	else
		dma_unmap_page(dev, dma_addr, size, DMA_TO_DEVICE);
//==========
       I will change map like this and use dma_map_single instead.

       Is this also seems to be not proper?

       Then how to do it?  add this before unmap? :
       dma_sync_single_for_device(dev, dma_addr, size, DMA_TO_DEVICE);

> 
> Robin.
>
Yong Wu July 29, 2015, 6:32 a.m. UTC | #10
On Mon, 2015-07-27 at 14:23 +0100, Robin Murphy wrote:
> On 16/07/15 10:04, Yong Wu wrote:
> > This patch adds support for mediatek m4u (MultiMedia Memory Management
> > Unit).
> >
> > Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> [...]
> > +static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
> > +{
> > +       struct mtk_iommu_domain *domain = cookie;
> > +       unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
> > +
> > +       dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
> > +                    size, DMA_TO_DEVICE);
> 
> Nit: this looks like it may as well be dma_map_single.
> 
> It would probably be worth following it with a matching unmap too, just 
> to avoid any possible leakage bugs (especially if this M4U ever appears 
> in a SoC supporting RAM above the 32-bit boundary).

About the map, I will read and try to follow your patch:
iommu/io-pgtable-arm: Allow appropriate DMA API use.

> 
>  > +}
>  > +
> [...]
> > +static int mtk_iommu_parse_dt(struct platform_device *pdev,
> > +                             struct mtk_iommu_data *data)
> > +{
> > +       struct device *dev = &pdev->dev;
> > +       struct device_node *ofnode;
> > +       struct resource *res;
> > +       int i;
> > +
> > +       ofnode = dev->of_node;
> > +
> > +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +       data->base = devm_ioremap_resource(&pdev->dev, res);
> > +       if (IS_ERR(data->base))
> > +               return PTR_ERR(data->base);
> > +
> > +       data->irq = platform_get_irq(pdev, 0);
> > +       if (data->irq < 0)
> > +               return data->irq;
> > +
> > +       data->bclk = devm_clk_get(dev, "bclk");
> > +       if (IS_ERR(data->bclk))
> > +               return PTR_ERR(data->bclk);
> > +
> > +       data->larb_nr = of_count_phandle_with_args(
> > +                                       ofnode, "mediatek,larb", NULL);
> > +       if (data->larb_nr < 0)
> > +               return data->larb_nr;
> > +
> > +       for (i = 0; i < data->larb_nr; i++) {
> > +               struct device_node *larbnode;
> > +               struct platform_device *plarbdev;
> > +
> > +               larbnode = of_parse_phandle(ofnode, "mediatek,larb", i);
> > +               if (!larbnode)
> > +                       return -EINVAL;
> > +
> > +               plarbdev = of_find_device_by_node(larbnode);
> > +               of_node_put(larbnode);
> > +               if (!plarbdev)
> > +                       return -EPROBE_DEFER;
> > +               data->larbdev[i] = &plarbdev->dev;
> > +       }
> 
> At a glance this seems like a job for of_parse_phandle_with_args, but I 
> may be missing something subtle.

It seems We can not use of_parse_phandle_with_args here.

The node of larb is.
//=========
larb0: larb@14021000 {
	compatible = "mediatek,mt8173-smi-larb";
	reg = <0 0x14021000 0 0x1000>;
	mediatek,smi = <&smi_common>;	
	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
	clocks = <&mmsys CLK_MM_SMI_LARB0>,
		 <&mmsys CLK_MM_SMI_LARB0>;
	clock-names = "apb", "smi";
};
//==========
  of_parse_phandle_with_args(ofnode,"mediatek,larb", "mediatek,smi",
&larb) will be wrong due to there is no item like "mediatek,smi = <1>;"
in larb.

And this code seems to be not simple if we use
of_parse_phandle_with_args. Both need a loop.

so I don't change it here, ok?
> 
> > +       return 0;
> > +}
> > +
> [...]
> > +static int mtk_iommu_init_domain_context(struct mtk_iommu_domain *dom)
> > +{
> > +       int ret;
> > +
> > +       if (dom->iop)
> > +               return 0;
> > +
> > +       spin_lock_init(&dom->pgtlock);
> > +       dom->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS |
> > +                       IO_PGTABLE_QUIRK_SHORT_SUPERSECTION |
> > +                       IO_PGTABLE_QUIRK_SHORT_MTK;
> > +       dom->cfg.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
> > +       dom->cfg.ias = 32;
> > +       dom->cfg.oas = 32;
> > +       dom->cfg.tlb = &mtk_iommu_gather_ops;
> > +
> > +       dom->iop = alloc_io_pgtable_ops(ARM_SHORT_DESC, &dom->cfg, dom);
> > +       if (!dom->iop) {
> > +               pr_err("Failed to alloc io pgtable\n");
> > +               return -EINVAL;
> > +       }
> > +
> > +       /* Update our support page sizes bitmap */
> > +       mtk_iommu_ops.pgsize_bitmap = dom->cfg.pgsize_bitmap;
> > +
> > +       ret = mtk_iommu_hw_init(dom);
> > +       if (ret)
> > +               free_io_pgtable_ops(dom->iop);
> > +
> > +       return ret;
> > +}
> 
> I don't see that you need the above function at all - since your 
> pagetable config is fixed and doesn't have any depency on which IOMMU 
> you're attaching to, can't you just do all of that straight away in 
> domain_alloc?

Yes. We could move it into domain_alloc.

> 
> > +static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
> > +{
> > +       struct mtk_iommu_domain *priv;
> > +
> > +       /* We only support unmanaged domains for now */
> > +       if (type != IOMMU_DOMAIN_UNMANAGED)
> > +               return NULL;
> 
> Have you had a chance to play with the latest DMA mapping series now 
> that I've integrated the default domain changes? I think if you handled 
> IOMMU_DOMAIN_DMA requests here and made them always return the 
> (preallocated) private domain, you should be able to get rid of the 
> tricks in attach_device completely.

  I can change it to this:
  if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
               return NULL;
 
  If always return the (preallocated) private domain, I have to use a
global variable to restore the preallocated domain here!.

  And It also will print "Incompatible range for DMA domain" and return
fail.
Could we return 0 instead of -EFAULT in iommu_dma_init_domain if the
domain is the same. 

> > +       priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> > +       if (!priv)
> > +               return NULL;
> > +
> > +       priv->domain.geometry.aperture_start = 0;
> > +       priv->domain.geometry.aperture_end = (1ULL << 32) - 1;
> 
> DMA_BIT_MASK(32) ?

Thanks.

> 
> > +       priv->domain.geometry.force_aperture = true;
> > +
> > +       return &priv->domain;
> > +}
> > +
> [...]
> > +static int mtk_iommu_add_device(struct device *dev)
> > +{
> > +       struct mtk_iommu_domain *mtkdom;
> > +       struct iommu_group *group;
> > +       struct mtk_iommu_client_priv *devhead;
> > +       int ret;
> > +
> > +       if (!dev->archdata.dma_ops)/* Not a iommu client device */
> > +               return -ENODEV;
> 
> I think archdata.dma_ops is the wrong thing to test here. It would be 
> better to use archdata.iommu, since you go on to dereference that 
> unconditionally anyway, plus then you only depend on your own of_xlate 
> behaviour, rather than some quirk of the arch code (which could quietly 
> change in future).

I will change archdata.iommu next time.
Current I used the dev->archdata.iommu of the iommu device(m4u device)
itself. then the m4u device will come here too. so I changed to
dev->archdata.dma_ops.

As before, If we use a global variable for the mtk_iommu_domain, we
could use archdata.iommu here.

> 
> > +       group = iommu_group_get(dev);
> > +       if (!group) {
> > +               group = iommu_group_alloc();
> > +               if (IS_ERR(group)) {
> > +                       dev_err(dev, "Failed to allocate IOMMU group\n");
> > +                       return PTR_ERR(group);
> > +               }
> > +       }
> > +
> > +       ret = iommu_group_add_device(group, dev);
> > +       if (ret) {
> > +               dev_err(dev, "Failed to add IOMMU group\n");
> > +               goto err_group_put;
> > +       }
> > +
> > +       /* get the mtk_iommu_domain from the iommu device */
> > +       devhead = dev->archdata.iommu;
> > +       mtkdom = devhead->imudev->archdata.iommu;
> > +       ret = iommu_attach_group(&mtkdom->domain, group);
> > +       if (ret)
> > +               dev_err(dev, "Failed to attach IOMMU group\n");
> > +
> > +err_group_put:
> > +       iommu_group_put(group);
> > +       return ret;
> > +}
> > +
> [...]
> > +static struct iommu_ops mtk_iommu_ops = {
> > +       .domain_alloc   = mtk_iommu_domain_alloc,
> > +       .domain_free    = mtk_iommu_domain_free,
> > +       .attach_dev     = mtk_iommu_attach_device,
> > +       .detach_dev     = mtk_iommu_detach_device,
> > +       .map            = mtk_iommu_map,
> > +       .unmap          = mtk_iommu_unmap,
> > +       .map_sg         = default_iommu_map_sg,
> > +       .iova_to_phys   = mtk_iommu_iova_to_phys,
> > +       .add_device     = mtk_iommu_add_device,
> > +       .of_xlate       = mtk_iommu_of_xlate,
> > +       .pgsize_bitmap  = -1UL,
> 
> As above, if you know the hardware only supports a single descriptor 
> format with a fixed set of page sizes, why not just represent that directly?

OK. I will write the fix page sizes here.
I wrote it following the arm-smmu.c:)

> 
> > +};
> > +
> [...]
> > +static int mtk_iommu_suspend(struct device *dev)
> > +{
> > +       struct mtk_iommu_domain *mtkdom = dev_get_drvdata(dev);
> > +       struct mtk_iommu_data *data = mtkdom->data;
> > +       void __iomem *base = data->base;
> > +       unsigned int i = 0;
> > +
> > +       data->reg[i++] = readl(base + REG_MMU_PT_BASE_ADDR);
> 
> Redundancy nit: any particular reason for saving this here rather than 
> simply restoring it from mtkdom->cfg.arm_short_cfg.ttbr[0] on resume?
> 
> > +       data->reg[i++] = readl(base + REG_MMU_STANDARD_AXI_MODE);
> > +       data->reg[i++] = readl(base + REG_MMU_DCM_DIS);
> > +       data->reg[i++] = readl(base + REG_MMU_CTRL_REG);
> > +       data->reg[i++] = readl(base + REG_MMU_IVRP_PADDR);
> > +       data->reg[i++] = readl(base + REG_MMU_INT_CONTROL0);
> > +       data->reg[i++] = readl(base + REG_MMU_INT_MAIN_CONTROL);
> 
> Nit: given that these are fairly arbitrary discontiguous registers so 
> you can't have a simple loop over the array, it might be clearer to 
> replace the array with an equivalent struct, e.g.:
> 
> struct mtk_iommu_suspend_regs {
> 	u32 standard_axi_mode;
> 	u32 dcm_dis;
> 	...
> }
> 
> 	...
> 	data->reg.dcm_dis = readl(base + REG_MMU_DCM_DIS);
> 	...
> 
> then since you refer to everything by name you don't have to worry about 
> the length and order of array elements if anything ever changes.

Good idea. Thanks very much.

> 
> > +       return 0;
> > +}
> > +
> > +static int mtk_iommu_resume(struct device *dev)
> > +{
> > +       struct mtk_iommu_domain *mtkdom = dev_get_drvdata(dev);
> > +       struct mtk_iommu_data *data = mtkdom->data;
> > +       void __iomem *base = data->base;
> > +       unsigned int i = 0;
> > +
> > +       writel(data->reg[i++], base + REG_MMU_PT_BASE_ADDR);
> > +       writel(data->reg[i++], base + REG_MMU_STANDARD_AXI_MODE);
> > +       writel(data->reg[i++], base + REG_MMU_DCM_DIS);
> > +       writel(data->reg[i++], base + REG_MMU_CTRL_REG);
> > +       writel(data->reg[i++], base + REG_MMU_IVRP_PADDR);
> > +       writel(data->reg[i++], base + REG_MMU_INT_CONTROL0);
> > +       writel(data->reg[i++], base + REG_MMU_INT_MAIN_CONTROL);
> > +       return 0;
> > +}
> 
> Other than that though, modulo the issues with the pagetable code I 
> think this part of the driver is shaping up quite nicely.
> 
> Robin.
>
Will Deacon July 29, 2015, 10:31 a.m. UTC | #11
On Wed, Jul 29, 2015 at 06:41:31AM +0100, Yong Wu wrote:
> On Mon, 2015-07-27 at 16:49 +0100, Robin Murphy wrote:
> > On 27/07/15 16:31, Russell King - ARM Linux wrote:
> > > On Mon, Jul 27, 2015 at 02:23:26PM +0100, Robin Murphy wrote:
> > >> On 16/07/15 10:04, Yong Wu wrote:
> > >>> This patch adds support for mediatek m4u (MultiMedia Memory Management
> > >>> Unit).
> > >>>
> > >>> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> > >> [...]
> > >>> +static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
> > >>> +{
> > >>> +       struct mtk_iommu_domain *domain = cookie;
> > >>> +       unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
> > >>> +
> > >>> +       dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
> > >>> +                    size, DMA_TO_DEVICE);
> > >>
> > >> Nit: this looks like it may as well be dma_map_single.
> > >>
> > >> It would probably be worth following it with a matching unmap too, just to
> > >> avoid any possible leakage bugs (especially if this M4U ever appears in a
> > >> SoC supporting RAM above the 32-bit boundary).
> > >
> > > Why not do the job properly?  Take a look at how I implemented the
> > > streaming DMA API on Tegra SMMU (patch set recently sent out earlier
> > > today).
> > >
> > > There's no need for hacks like dma_map_page() (and discarding it's
> > > return value) or dma_map_page() followed by dma_unmap_page().
> > 
> > Indeed, as it happens I do have a branch where I prototyped that for the 
> > long-descriptor io-pgtable-arm code a while ago; this discussion has 
> > prompted me to dig it up again. Stay tuned, folks...
> 
> Hi Russell, Robin,
> 
>      From I see in arm-smmu-v3.c in v4.2-rc1, 
>      
>      The flush_pgtable seems like this:
> //==========
> 	dma_addr_t dma_addr;
> 
> 	dma_addr = dma_map_page(dev, ptr, size, DMA_TO_DEVICE);
> 
> 	if (dma_mapping_error(dev, dma_addr))
> 		dev_err(dev, "failed to flush pgtable at %p\n", ptr);
> 	else
> 		dma_unmap_page(dev, dma_addr, size, DMA_TO_DEVICE);
> //==========
>        I will change map like this and use dma_map_single instead.
> 
>        Is this also seems to be not proper?
> 
>        Then how to do it?  add this before unmap? :
>        dma_sync_single_for_device(dev, dma_addr, size, DMA_TO_DEVICE);

Robin's proposed a series fixing this in the io-pgtable code:

  http://lists.linuxfoundation.org/pipermail/iommu/2015-July/013821.html

which is currently under review. Please take a look and give comments!
Once merged, the code you cite above will be removed.

Will

Patch
diff mbox

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index f50dbf3..3178c12 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -386,4 +386,17 @@  config ARM_SMMU_V3
 	  Say Y here if your system includes an IOMMU device implementing
 	  the ARM SMMUv3 architecture.
 
+config MTK_IOMMU
+	bool "MTK IOMMU Support"
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	select IOMMU_API
+	select IOMMU_DMA
+	select IOMMU_IO_PGTABLE_SHORT
+	select MEMORY
+	select MTK_SMI
+	help
+	  Support for the IOMMUs on certain Mediatek SOCs.
+
+	  If unsure, say N here.
+
 endif # IOMMU_SUPPORT
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 06df3e6..f4f2f2c 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -21,6 +21,7 @@  obj-$(CONFIG_ROCKCHIP_IOMMU) += rockchip-iommu.o
 obj-$(CONFIG_TEGRA_IOMMU_GART) += tegra-gart.o
 obj-$(CONFIG_TEGRA_IOMMU_SMMU) += tegra-smmu.o
 obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o
+obj-$(CONFIG_MTK_IOMMU) += mtk_iommu.o
 obj-$(CONFIG_SHMOBILE_IOMMU) += shmobile-iommu.o
 obj-$(CONFIG_SHMOBILE_IPMMU) += shmobile-ipmmu.o
 obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
new file mode 100644
index 0000000..c1c90e6
--- /dev/null
+++ b/drivers/iommu/mtk_iommu.c
@@ -0,0 +1,724 @@ 
+/*
+ * Copyright (c) 2014-2015 MediaTek Inc.
+ * Author: Yong Wu <yong.wu@mediatek.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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/dma-iommu.h>
+#include <linux/of_iommu.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/list.h>
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <asm/cacheflush.h>
+#include <soc/mediatek/smi.h>
+
+#include "io-pgtable.h"
+
+#define REG_MMU_PT_BASE_ADDR			0x000
+
+#define REG_MMU_INVALIDATE			0x020
+#define F_ALL_INVLD				0x2
+#define F_MMU_INV_RANGE				0x1
+
+#define REG_MMU_INVLD_START_A			0x024
+#define REG_MMU_INVLD_END_A			0x028
+
+#define REG_MMU_INV_SEL				0x038
+#define F_INVLD_EN0				BIT(0)
+#define F_INVLD_EN1				BIT(1)
+
+#define REG_MMU_STANDARD_AXI_MODE		0x048
+#define REG_MMU_DCM_DIS				0x050
+
+#define REG_MMU_CTRL_REG			0x110
+#define F_MMU_PREFETCH_RT_REPLACE_MOD		BIT(4)
+#define F_MMU_TF_PROTECT_SEL(prot)		(((prot) & 0x3) << 5)
+#define F_COHERENCE_EN				BIT(8)
+
+#define REG_MMU_IVRP_PADDR			0x114
+#define F_MMU_IVRP_PA_SET(pa)			((pa) >> 1)
+
+#define REG_MMU_INT_CONTROL0			0x120
+#define F_L2_MULIT_HIT_EN			BIT(0)
+#define F_TABLE_WALK_FAULT_INT_EN		BIT(1)
+#define F_PREETCH_FIFO_OVERFLOW_INT_EN		BIT(2)
+#define F_MISS_FIFO_OVERFLOW_INT_EN		BIT(3)
+#define F_PREFETCH_FIFO_ERR_INT_EN		BIT(5)
+#define F_MISS_FIFO_ERR_INT_EN			BIT(6)
+#define F_INT_L2_CLR_BIT			BIT(12)
+
+#define REG_MMU_INT_MAIN_CONTROL		0x124
+#define F_INT_TRANSLATION_FAULT			BIT(0)
+#define F_INT_MAIN_MULTI_HIT_FAULT		BIT(1)
+#define F_INT_INVALID_PA_FAULT			BIT(2)
+#define F_INT_ENTRY_REPLACEMENT_FAULT		BIT(3)
+#define F_INT_TLB_MISS_FAULT			BIT(4)
+#define F_INT_MISS_TRANSATION_FIFO_FAULT	BIT(5)
+#define F_INT_PRETETCH_TRANSATION_FIFO_FAULT	BIT(6)
+
+#define REG_MMU_CPE_DONE			0x12C
+
+#define REG_MMU_FAULT_ST1			0x134
+
+#define REG_MMU_FAULT_VA			0x13c
+#define F_MMU_FAULT_VA_MSK			0xfffff000
+#define F_MMU_FAULT_VA_WRITE_BIT		BIT(1)
+#define F_MMU_FAULT_VA_LAYER_BIT		BIT(0)
+
+#define REG_MMU_INVLD_PA			0x140
+#define REG_MMU_INT_ID				0x150
+#define F_MMU0_INT_ID_LARB_ID(a)		(((a) >> 7) & 0x7)
+#define F_MMU0_INT_ID_PORT_ID(a)		(((a) >> 2) & 0x1f)
+
+#define MTK_PROTECT_PA_ALIGN			128
+#define MTK_IOMMU_LARB_MAX_NR			8
+#define MTK_IOMMU_REG_NR			10
+
+struct mtk_iommu_data {
+	void __iomem		*base;
+	int			irq;
+	struct device		*dev;
+	struct device		*larbdev[MTK_IOMMU_LARB_MAX_NR];
+	struct clk		*bclk;
+	phys_addr_t		protect_base; /* protect memory base */
+	int			larb_nr;      /* local arbiter number */
+	u32			reg[MTK_IOMMU_REG_NR];
+};
+
+struct mtk_iommu_domain {
+	struct imu_pgd_t	*pgd;
+	spinlock_t		pgtlock; /* lock for modifying page table */
+
+	struct io_pgtable_cfg   cfg;
+	struct io_pgtable_ops   *iop;
+
+	struct mtk_iommu_data   *data;
+	struct iommu_domain	domain;
+};
+
+struct mtk_iommu_client_priv {
+	struct list_head	client;
+	unsigned int		larbid;
+	unsigned int		portid;
+	struct device		*imudev;
+};
+
+static struct iommu_ops mtk_iommu_ops;
+
+static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
+{
+	return container_of(dom, struct mtk_iommu_domain, domain);
+}
+
+static void mtk_iommu_clear_intr(const struct mtk_iommu_data *data)
+{
+	u32 val;
+
+	val = readl(data->base + REG_MMU_INT_CONTROL0);
+	val |= F_INT_L2_CLR_BIT;
+	writel(val, data->base + REG_MMU_INT_CONTROL0);
+}
+
+static void mtk_iommu_tlb_flush_all(void *cookie)
+{
+	struct mtk_iommu_domain *domain = cookie;
+	void __iomem *base;
+
+	base = domain->data->base;
+	writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
+	writel(F_ALL_INVLD, base + REG_MMU_INVALIDATE);
+}
+
+static void mtk_iommu_tlb_add_flush(unsigned long iova, size_t size,
+				    bool leaf, void *cookie)
+{
+	struct mtk_iommu_domain *domain = cookie;
+	void __iomem *base = domain->data->base;
+	unsigned int iova_start = iova, iova_end = iova + size - 1;
+
+	writel(F_INVLD_EN1 | F_INVLD_EN0, base + REG_MMU_INV_SEL);
+
+	writel(iova_start, base + REG_MMU_INVLD_START_A);
+	writel(iova_end, base + REG_MMU_INVLD_END_A);
+	writel(F_MMU_INV_RANGE, base + REG_MMU_INVALIDATE);
+}
+
+static void mtk_iommu_tlb_sync(void *cookie)
+{
+	struct mtk_iommu_domain *domain = cookie;
+	void __iomem *base = domain->data->base;
+	int ret;
+	u32 tmp;
+
+	ret = readl_poll_timeout_atomic(base + REG_MMU_CPE_DONE, tmp,
+					tmp != 0, 10, 1000000);
+	if (ret) {
+		dev_warn(domain->data->dev,
+			 "Partial TLB flush timed out, falling back to full flush\n");
+		mtk_iommu_tlb_flush_all(cookie);
+	}
+	writel(0, base + REG_MMU_CPE_DONE);
+}
+
+static void mtk_iommu_flush_pgtable(void *ptr, size_t size, void *cookie)
+{
+	struct mtk_iommu_domain *domain = cookie;
+	unsigned long offset = (unsigned long)ptr & ~PAGE_MASK;
+
+	dma_map_page(domain->data->dev, virt_to_page(ptr), offset,
+		     size, DMA_TO_DEVICE);
+}
+
+static struct iommu_gather_ops mtk_iommu_gather_ops = {
+	.tlb_flush_all = mtk_iommu_tlb_flush_all,
+	.tlb_add_flush = mtk_iommu_tlb_add_flush,
+	.tlb_sync = mtk_iommu_tlb_sync,
+	.flush_pgtable = mtk_iommu_flush_pgtable,
+};
+
+static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
+{
+	struct mtk_iommu_domain *mtkdom = dev_id;
+	struct mtk_iommu_data *data = mtkdom->data;
+	u32 int_state, regval, fault_iova, fault_pa;
+	unsigned int fault_larb, fault_port;
+	bool layer, write;
+
+	int_state = readl(data->base + REG_MMU_FAULT_ST1);
+
+	/* read error info from registers */
+	fault_iova = readl(data->base + REG_MMU_FAULT_VA);
+	layer = fault_iova & F_MMU_FAULT_VA_LAYER_BIT;
+	write = fault_iova & F_MMU_FAULT_VA_WRITE_BIT;
+	fault_iova &= F_MMU_FAULT_VA_MSK;
+	fault_pa = readl(data->base + REG_MMU_INVLD_PA);
+	regval = readl(data->base + REG_MMU_INT_ID);
+	fault_larb = F_MMU0_INT_ID_LARB_ID(regval);
+	fault_port = F_MMU0_INT_ID_PORT_ID(regval);
+
+	if (report_iommu_fault(&mtkdom->domain, data->dev, fault_iova,
+			       write ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ)) {
+		dev_err_ratelimited(
+			data->dev,
+			"fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d layer=%d %s\n",
+			int_state, fault_iova, fault_pa, fault_larb, fault_port,
+			layer, write ? "write" : "read");
+	}
+
+	mtk_iommu_tlb_flush_all(mtkdom);
+	mtk_iommu_clear_intr(data);
+
+	return IRQ_HANDLED;
+}
+
+static int mtk_iommu_parse_dt(struct platform_device *pdev,
+			      struct mtk_iommu_data *data)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *ofnode;
+	struct resource *res;
+	int i;
+
+	ofnode = dev->of_node;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	data->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(data->base))
+		return PTR_ERR(data->base);
+
+	data->irq = platform_get_irq(pdev, 0);
+	if (data->irq < 0)
+		return data->irq;
+
+	data->bclk = devm_clk_get(dev, "bclk");
+	if (IS_ERR(data->bclk))
+		return PTR_ERR(data->bclk);
+
+	data->larb_nr = of_count_phandle_with_args(
+					ofnode, "mediatek,larb", NULL);
+	if (data->larb_nr < 0)
+		return data->larb_nr;
+
+	for (i = 0; i < data->larb_nr; i++) {
+		struct device_node *larbnode;
+		struct platform_device *plarbdev;
+
+		larbnode = of_parse_phandle(ofnode, "mediatek,larb", i);
+		if (!larbnode)
+			return -EINVAL;
+
+		plarbdev = of_find_device_by_node(larbnode);
+		of_node_put(larbnode);
+		if (!plarbdev)
+			return -EPROBE_DEFER;
+		data->larbdev[i] = &plarbdev->dev;
+	}
+
+	return 0;
+}
+
+static int mtk_iommu_hw_init(const struct mtk_iommu_domain *mtkdom)
+{
+	struct mtk_iommu_data *data = mtkdom->data;
+	void __iomem *base = data->base;
+	u32 regval;
+	int ret = 0;
+
+	ret = clk_prepare_enable(data->bclk);
+	if (ret) {
+		dev_err(data->dev, "Failed to enable iommu clk(%d)\n", ret);
+		return ret;
+	}
+
+	writel(mtkdom->cfg.arm_short_cfg.ttbr[0], base + REG_MMU_PT_BASE_ADDR);
+
+	regval = F_MMU_PREFETCH_RT_REPLACE_MOD |
+		F_MMU_TF_PROTECT_SEL(2) |
+		F_COHERENCE_EN;
+	writel(regval, base + REG_MMU_CTRL_REG);
+
+	regval = F_L2_MULIT_HIT_EN |
+		F_TABLE_WALK_FAULT_INT_EN |
+		F_PREETCH_FIFO_OVERFLOW_INT_EN |
+		F_MISS_FIFO_OVERFLOW_INT_EN |
+		F_PREFETCH_FIFO_ERR_INT_EN |
+		F_MISS_FIFO_ERR_INT_EN;
+	writel(regval, base + REG_MMU_INT_CONTROL0);
+
+	regval = F_INT_TRANSLATION_FAULT |
+		F_INT_MAIN_MULTI_HIT_FAULT |
+		F_INT_INVALID_PA_FAULT |
+		F_INT_ENTRY_REPLACEMENT_FAULT |
+		F_INT_TLB_MISS_FAULT |
+		F_INT_MISS_TRANSATION_FIFO_FAULT |
+		F_INT_PRETETCH_TRANSATION_FIFO_FAULT;
+	writel(regval, base + REG_MMU_INT_MAIN_CONTROL);
+
+	regval = ALIGN(data->protect_base, MTK_PROTECT_PA_ALIGN);
+	regval = F_MMU_IVRP_PA_SET(regval);
+	writel(regval, base + REG_MMU_IVRP_PADDR);
+
+	writel(0, base + REG_MMU_DCM_DIS);
+	writel(0, base + REG_MMU_STANDARD_AXI_MODE);
+
+	if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
+			     dev_name(data->dev), (void *)mtkdom)) {
+		writel(0, base + REG_MMU_PT_BASE_ADDR);
+		clk_disable_unprepare(data->bclk);
+		dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int mtk_iommu_config(struct mtk_iommu_domain *mtkdom,
+			    struct device *dev, bool enable)
+{
+	struct mtk_iommu_data *data = mtkdom->data;
+	struct mtk_iommu_client_priv *head, *cur, *next;
+
+	head = dev->archdata.iommu;
+	list_for_each_entry_safe(cur, next, &head->client, client) {
+		if (cur->larbid >= data->larb_nr) {
+			dev_err(data->dev, "Invalid larb:%d\n", cur->larbid);
+			return -EINVAL;
+		}
+
+		if (enable) {
+			mtk_smi_config_port(data->larbdev[cur->larbid],
+					    cur->portid, true);
+		} else {
+			mtk_smi_config_port(data->larbdev[cur->larbid],
+					    cur->portid, false);
+			list_del(&cur->client);
+			kfree(cur);
+		}
+	}
+
+	if (!enable)
+		kfree(head);
+	return 0;
+}
+
+static int mtk_iommu_init_domain_context(struct mtk_iommu_domain *dom)
+{
+	int ret;
+
+	if (dom->iop)
+		return 0;
+
+	spin_lock_init(&dom->pgtlock);
+	dom->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS |
+			IO_PGTABLE_QUIRK_SHORT_SUPERSECTION |
+			IO_PGTABLE_QUIRK_SHORT_MTK;
+	dom->cfg.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
+	dom->cfg.ias = 32;
+	dom->cfg.oas = 32;
+	dom->cfg.tlb = &mtk_iommu_gather_ops;
+
+	dom->iop = alloc_io_pgtable_ops(ARM_SHORT_DESC, &dom->cfg, dom);
+	if (!dom->iop) {
+		pr_err("Failed to alloc io pgtable\n");
+		return -EINVAL;
+	}
+
+	/* Update our support page sizes bitmap */
+	mtk_iommu_ops.pgsize_bitmap = dom->cfg.pgsize_bitmap;
+
+	ret = mtk_iommu_hw_init(dom);
+	if (ret)
+		free_io_pgtable_ops(dom->iop);
+
+	return ret;
+}
+
+static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
+{
+	struct mtk_iommu_domain *priv;
+
+	/* We only support unmanaged domains for now */
+	if (type != IOMMU_DOMAIN_UNMANAGED)
+		return NULL;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return NULL;
+
+	priv->domain.geometry.aperture_start = 0;
+	priv->domain.geometry.aperture_end = (1ULL << 32) - 1;
+	priv->domain.geometry.force_aperture = true;
+
+	return &priv->domain;
+}
+
+static void mtk_iommu_domain_free(struct iommu_domain *domain)
+{
+	kfree(to_mtk_domain(domain));
+}
+
+static int mtk_iommu_attach_device(struct iommu_domain *domain,
+				   struct device *dev)
+{
+	struct mtk_iommu_domain *priv = to_mtk_domain(domain);
+	struct iommu_group *group;
+	struct mtk_iommu_client_priv *devpriv;
+	struct device *imudev;
+	int ret;
+
+	devpriv = dev->archdata.iommu;
+	imudev = devpriv->imudev;
+
+	/*
+	 * Reserve one iommu domain as the m4u domain which
+	 * all Multimedia modules share and free the others.
+	 */
+	if (!imudev->archdata.iommu)
+		imudev->archdata.iommu = priv;
+	else if (imudev->archdata.iommu != priv)
+		iommu_domain_free(domain);
+
+	group = iommu_group_get(dev);
+	if (!group)
+		return 0;
+	iommu_group_put(group);
+
+	ret = mtk_iommu_init_domain_context(priv);
+	if (ret)
+		return ret;
+
+	return mtk_iommu_config(priv, dev, true);;
+}
+
+static void mtk_iommu_detach_device(struct iommu_domain *domain,
+				    struct device *dev)
+{
+	mtk_iommu_config(to_mtk_domain(domain), dev, false);
+}
+
+static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
+			 phys_addr_t paddr, size_t size, int prot)
+{
+	struct mtk_iommu_domain *priv = to_mtk_domain(domain);
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&priv->pgtlock, flags);
+	ret = priv->iop->map(priv->iop, iova, paddr, size, prot);
+	spin_unlock_irqrestore(&priv->pgtlock, flags);
+
+	return ret;
+}
+
+static size_t mtk_iommu_unmap(struct iommu_domain *domain,
+			      unsigned long iova, size_t size)
+{
+	struct mtk_iommu_domain *priv = to_mtk_domain(domain);
+	unsigned long flags;
+	size_t unmapsize;
+
+	spin_lock_irqsave(&priv->pgtlock, flags);
+	unmapsize = priv->iop->unmap(priv->iop, iova, size);
+	spin_unlock_irqrestore(&priv->pgtlock, flags);
+
+	return unmapsize;
+}
+
+static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
+					  dma_addr_t iova)
+{
+	struct mtk_iommu_domain *priv = to_mtk_domain(domain);
+	unsigned long flags;
+	phys_addr_t pa;
+
+	spin_lock_irqsave(&priv->pgtlock, flags);
+	pa = priv->iop->iova_to_phys(priv->iop, iova);
+	spin_unlock_irqrestore(&priv->pgtlock, flags);
+
+	return pa;
+}
+
+static int mtk_iommu_add_device(struct device *dev)
+{
+	struct mtk_iommu_domain *mtkdom;
+	struct iommu_group *group;
+	struct mtk_iommu_client_priv *devhead;
+	int ret;
+
+	if (!dev->archdata.dma_ops)/* Not a iommu client device */
+		return -ENODEV;
+
+	group = iommu_group_get(dev);
+	if (!group) {
+		group = iommu_group_alloc();
+		if (IS_ERR(group)) {
+			dev_err(dev, "Failed to allocate IOMMU group\n");
+			return PTR_ERR(group);
+		}
+	}
+
+	ret = iommu_group_add_device(group, dev);
+	if (ret) {
+		dev_err(dev, "Failed to add IOMMU group\n");
+		goto err_group_put;
+	}
+
+	/* get the mtk_iommu_domain from the iommu device */
+	devhead = dev->archdata.iommu;
+	mtkdom = devhead->imudev->archdata.iommu;
+	ret = iommu_attach_group(&mtkdom->domain, group);
+	if (ret)
+		dev_err(dev, "Failed to attach IOMMU group\n");
+
+err_group_put:
+	iommu_group_put(group);
+	return ret;
+}
+
+int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
+{
+	struct mtk_iommu_client_priv *head, *priv, *next;
+	struct platform_device *imupdev;
+	struct device *imudev;
+
+	if (args->args_count != 2) {
+		dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
+			args->args_count);
+		return -EINVAL;
+	}
+
+	if (!dev->archdata.iommu) {
+		/* Get the iommu device */
+		imupdev = of_find_device_by_node(args->np);
+		of_node_put(args->np);
+		if (WARN_ON(!imupdev))
+			return -EINVAL;
+		imudev = &imupdev->dev;
+
+		head = kzalloc(sizeof(*head), GFP_KERNEL);
+		if (!head)
+			return -ENOMEM;
+
+		dev->archdata.iommu = head;
+		INIT_LIST_HEAD(&head->client);
+		head->imudev = imudev;
+	} else {
+		head = dev->archdata.iommu;
+	}
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		goto err_free_mem;
+
+	priv->larbid = args->args[0];
+	priv->portid = args->args[1];
+	list_add_tail(&priv->client, &head->client);
+
+	return 0;
+
+err_free_mem:
+	list_for_each_entry_safe(priv, next, &head->client, client)
+		kfree(priv);
+	kfree(head);
+	dev->archdata.iommu = NULL;
+	return -ENOMEM;
+}
+
+static struct iommu_ops mtk_iommu_ops = {
+	.domain_alloc	= mtk_iommu_domain_alloc,
+	.domain_free	= mtk_iommu_domain_free,
+	.attach_dev	= mtk_iommu_attach_device,
+	.detach_dev	= mtk_iommu_detach_device,
+	.map		= mtk_iommu_map,
+	.unmap		= mtk_iommu_unmap,
+	.map_sg		= default_iommu_map_sg,
+	.iova_to_phys	= mtk_iommu_iova_to_phys,
+	.add_device	= mtk_iommu_add_device,
+	.of_xlate	= mtk_iommu_of_xlate,
+	.pgsize_bitmap	= -1UL,
+};
+
+static const struct of_device_id mtk_iommu_of_ids[] = {
+	{ .compatible = "mediatek,mt8173-m4u", },
+	{}
+};
+
+static int mtk_iommu_init_fn(struct device_node *np)
+{
+	struct platform_device *pdev;
+
+	pdev = of_platform_device_create(np, NULL, platform_bus_type.dev_root);
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
+
+	of_iommu_set_ops(np, &mtk_iommu_ops);
+
+	return 0;
+}
+
+IOMMU_OF_DECLARE(mtkm4u, "mediatek,mt8173-m4u", mtk_iommu_init_fn);
+
+static int mtk_iommu_probe(struct platform_device *pdev)
+{
+	struct mtk_iommu_domain	*mtkdom;
+	struct mtk_iommu_data   *data;
+	struct device           *dev = &pdev->dev;
+	void __iomem	        *protect;
+	int                     ret;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	/* Protect memory. HW will access here while translation fault.*/
+	protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2, GFP_KERNEL);
+	if (!protect)
+		return -ENOMEM;
+	data->protect_base = virt_to_phys(protect);
+
+	ret = mtk_iommu_parse_dt(pdev, data);
+	if (ret)
+		return ret;
+
+	mtkdom = dev->archdata.iommu;
+	if (!mtkdom)/* There is no iommu client device */
+		return 0;
+
+	mtkdom->data = data;
+	data->dev = dev;
+	dev_set_drvdata(dev, mtkdom);
+
+	return 0;
+}
+
+static int mtk_iommu_remove(struct platform_device *pdev)
+{
+	struct mtk_iommu_domain *mtkdom = dev_get_drvdata(&pdev->dev);
+
+	/* Destroy domain context */
+	free_io_pgtable_ops(mtkdom->iop);
+
+	clk_disable_unprepare(mtkdom->data->bclk);
+	return 0;
+}
+
+static int mtk_iommu_suspend(struct device *dev)
+{
+	struct mtk_iommu_domain *mtkdom = dev_get_drvdata(dev);
+	struct mtk_iommu_data *data = mtkdom->data;
+	void __iomem *base = data->base;
+	unsigned int i = 0;
+
+	data->reg[i++] = readl(base + REG_MMU_PT_BASE_ADDR);
+	data->reg[i++] = readl(base + REG_MMU_STANDARD_AXI_MODE);
+	data->reg[i++] = readl(base + REG_MMU_DCM_DIS);
+	data->reg[i++] = readl(base + REG_MMU_CTRL_REG);
+	data->reg[i++] = readl(base + REG_MMU_IVRP_PADDR);
+	data->reg[i++] = readl(base + REG_MMU_INT_CONTROL0);
+	data->reg[i++] = readl(base + REG_MMU_INT_MAIN_CONTROL);
+	return 0;
+}
+
+static int mtk_iommu_resume(struct device *dev)
+{
+	struct mtk_iommu_domain *mtkdom = dev_get_drvdata(dev);
+	struct mtk_iommu_data *data = mtkdom->data;
+	void __iomem *base = data->base;
+	unsigned int i = 0;
+
+	writel(data->reg[i++], base + REG_MMU_PT_BASE_ADDR);
+	writel(data->reg[i++], base + REG_MMU_STANDARD_AXI_MODE);
+	writel(data->reg[i++], base + REG_MMU_DCM_DIS);
+	writel(data->reg[i++], base + REG_MMU_CTRL_REG);
+	writel(data->reg[i++], base + REG_MMU_IVRP_PADDR);
+	writel(data->reg[i++], base + REG_MMU_INT_CONTROL0);
+	writel(data->reg[i++], base + REG_MMU_INT_MAIN_CONTROL);
+	return 0;
+}
+
+const struct dev_pm_ops mtk_iommu_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
+};
+
+static struct platform_driver mtk_iommu_driver = {
+	.probe	= mtk_iommu_probe,
+	.remove	= mtk_iommu_remove,
+	.driver	= {
+		.name = "mtk-iommu",
+		.of_match_table = mtk_iommu_of_ids,
+		.pm = &mtk_iommu_pm_ops,
+	}
+};
+
+static int __init mtk_iommu_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&mtk_iommu_driver);
+	if (ret) {
+		pr_err("%s: Failed to register driver\n", __func__);
+		return ret;
+	}
+
+	if (!iommu_present(&platform_bus_type))
+		bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
+
+	return 0;
+}
+
+subsys_initcall(mtk_iommu_init);