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iommu/mediatek: Merge 2 M4U HWs into one iommu domain
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In theory, If there are 2 M4U HWs, there should be 2 IOMMU domains.
But one IOMMU domain(4GB iova range) is enough for us currently,
It's unnecessary to maintain 2 pagetables.

Besides, This patch can simplify our consumer code largely. They don't
need map a iova range from one domain into another, They can share the
iova address easily.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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@YongWu-HF @joergroedel
YongWu-HF authored and joergroedel committed Aug 22, 2017
1 parent e6dec92 commit 7c3a2ec
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Showing 2 changed files with 70 additions and 24 deletions.
92 changes: 68 additions & 24 deletions drivers/iommu/mtk_iommu.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -114,6 +114,27 @@ struct mtk_iommu_domain {

static struct iommu_ops mtk_iommu_ops;

static LIST_HEAD(m4ulist); /* List all the M4U HWs */

#define for_each_m4u(data) list_for_each_entry(data, &m4ulist, list)

/*
* There may be 1 or 2 M4U HWs, But we always expect they are in the same domain
* for the performance.
*
* Here always return the mtk_iommu_data of the first probed M4U where the
* iommu domain information is recorded.
*/
static struct mtk_iommu_data *mtk_iommu_get_m4u_data(void)
{
struct mtk_iommu_data *data;

for_each_m4u(data)
return data;

return NULL;
}

static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
{
return container_of(dom, struct mtk_iommu_domain, domain);
Expand All @@ -123,9 +144,12 @@ static void mtk_iommu_tlb_flush_all(void *cookie)
{
struct mtk_iommu_data *data = cookie;

writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0, data->base + REG_MMU_INV_SEL);
writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
wmb(); /* Make sure the tlb flush all done */
for_each_m4u(data) {
writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
data->base + REG_MMU_INV_SEL);
writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
wmb(); /* Make sure the tlb flush all done */
}
}

static void mtk_iommu_tlb_add_flush_nosync(unsigned long iova, size_t size,
Expand All @@ -134,12 +158,17 @@ static void mtk_iommu_tlb_add_flush_nosync(unsigned long iova, size_t size,
{
struct mtk_iommu_data *data = cookie;

writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0, data->base + REG_MMU_INV_SEL);
for_each_m4u(data) {
writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
data->base + REG_MMU_INV_SEL);

writel_relaxed(iova, data->base + REG_MMU_INVLD_START_A);
writel_relaxed(iova + size - 1, data->base + REG_MMU_INVLD_END_A);
writel_relaxed(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);
data->tlb_flush_active = true;
writel_relaxed(iova, data->base + REG_MMU_INVLD_START_A);
writel_relaxed(iova + size - 1,
data->base + REG_MMU_INVLD_END_A);
writel_relaxed(F_MMU_INV_RANGE,
data->base + REG_MMU_INVALIDATE);
data->tlb_flush_active = true;
}
}

static void mtk_iommu_tlb_sync(void *cookie)
Expand All @@ -148,20 +177,22 @@ static void mtk_iommu_tlb_sync(void *cookie)
int ret;
u32 tmp;

/* Avoid timing out if there's nothing to wait for */
if (!data->tlb_flush_active)
return;
for_each_m4u(data) {
/* Avoid timing out if there's nothing to wait for */
if (!data->tlb_flush_active)
return;

ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE, tmp,
tmp != 0, 10, 100000);
if (ret) {
dev_warn(data->dev,
"Partial TLB flush timed out, falling back to full flush\n");
mtk_iommu_tlb_flush_all(cookie);
ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
tmp, tmp != 0, 10, 100000);
if (ret) {
dev_warn(data->dev,
"Partial TLB flush timed out, falling back to full flush\n");
mtk_iommu_tlb_flush_all(cookie);
}
/* Clear the CPE status */
writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
data->tlb_flush_active = false;
}
/* Clear the CPE status */
writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
data->tlb_flush_active = false;
}

static const struct iommu_gather_ops mtk_iommu_gather_ops = {
Expand Down Expand Up @@ -298,10 +329,11 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,
struct device *dev)
{
struct mtk_iommu_domain *dom = to_mtk_domain(domain);
struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
struct mtk_iommu_data *curdata = dev->iommu_fwspec->iommu_priv;
struct mtk_iommu_data *data = mtk_iommu_get_m4u_data();
int ret;

if (!data)
if (!data || !curdata)
return -ENODEV;

if (!data->m4u_dom) {
Expand All @@ -313,7 +345,17 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,
}
}

mtk_iommu_config(data, dev, true);
/*
* Update the pgtable base address register of another M4U HW with the
* existed pgtable if there are more than one M4U HW.
*/
if (!curdata->m4u_dom) {
curdata->m4u_dom = data->m4u_dom;
writel(data->m4u_dom->cfg.arm_v7s_cfg.ttbr[0],
curdata->base + REG_MMU_PT_BASE_ADDR);
}

mtk_iommu_config(curdata, dev, true);
return 0;
}

Expand Down Expand Up @@ -405,7 +447,7 @@ static void mtk_iommu_remove_device(struct device *dev)

static struct iommu_group *mtk_iommu_device_group(struct device *dev)
{
struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
struct mtk_iommu_data *data = mtk_iommu_get_m4u_data();

if (!data)
return ERR_PTR(-ENODEV);
Expand Down Expand Up @@ -604,6 +646,8 @@ static int mtk_iommu_probe(struct platform_device *pdev)
if (ret)
return ret;

list_add_tail(&data->list, &m4ulist);

if (!iommu_present(&platform_bus_type))
bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);

Expand Down
2 changes: 2 additions & 0 deletions drivers/iommu/mtk_iommu.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -57,6 +57,8 @@ struct mtk_iommu_data {

struct iommu_device iommu;
enum mtk_iommu_plat m4u_plat;

struct list_head list;
};

static inline int compare_of(struct device *dev, void *data)
Expand Down

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