[PATCH 12/13] iommu/mediatek: Change single domain to multiple domains

From: Chao Hao
Date: Mon Oct 28 2019 - 04:29:19 EST


Based on one mtk_iommu_domain, this patch supports multiple
mtk_iommu_domains to realize different iova regions.

Every module has one smi_larb port, so we can create different
mtk_iommu_domains by smi_larb port define. So we will add port_mask
variable to mtk_domain_data, if some modules need special iova regions,
they can write smi_larb port which corresponding to themselves to
post_mask variable and specify the start and end address of iova region.
The form of port_mask can use "MTK_M4U_ID(larb, port)", larb and port can
refer to "mtxxxx-larb-port.h(ex: mt6779-larb-port.h)" file.

The architecture diagram is as below:

mtk_iommu_pgtable
|
mtk_domain_data
|
-------------------------------------------------
| | |
mtk_iommu_domain1 mtk_iommu_domain2 mtk_iommu_domain3

Signed-off-by: Chao Hao <chao.hao@xxxxxxxxxxxx>
---
drivers/iommu/mtk_iommu.c | 48 +++++++++++++++++++++++++++++++++------
drivers/iommu/mtk_iommu.h | 11 ++++++++-
2 files changed, 51 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index c0cd7da71c2c..c33ea55a1841 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -130,6 +130,8 @@ struct mtk_iommu_pgtable {
struct io_pgtable_ops *iop;
struct device *init_dev;
struct list_head m4u_dom_v2;
+ spinlock_t domain_lock; /* lock for domain count */
+ u32 domain_count;
const struct mtk_domain_data *dom_region;
};

@@ -172,11 +174,15 @@ static LIST_HEAD(m4ulist); /* List all the M4U HWs */
static u32 get_domain_id(struct mtk_iommu_data *data, u32 portid)
{
u32 dom_id = 0;
- int i;
+ const struct mtk_domain_data *mtk_dom_array = data->plat_data->dom_data;
+ int i, j;

- /* only support one mtk_iommu_domain currently(dom_cnt = 1) */
- for (i = 0; i < data->plat_data->dom_cnt; i++)
- return i;
+ for (i = 0; i < data->plat_data->dom_cnt; i++) {
+ for (j = 0; j < MTK_MAX_PORT_NUM; j++) {
+ if (portid == mtk_dom_array[i].port_mask[j])
+ return i;
+ }
+ }

return dom_id;
}
@@ -416,6 +422,8 @@ static struct mtk_iommu_pgtable *create_pgtable(struct mtk_iommu_data *data)
if (!pgtable)
return ERR_PTR(-ENOMEM);

+ spin_lock_init(&pgtable->domain_lock);
+ pgtable->domain_count = 0;
INIT_LIST_HEAD(&pgtable->m4u_dom_v2);

pgtable->cfg = (struct io_pgtable_cfg) {
@@ -476,6 +484,7 @@ static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
struct mtk_iommu_data *data;
struct mtk_iommu_domain *dom;
struct device *dev;
+ unsigned long flags;

if (type != IOMMU_DOMAIN_DMA)
return NULL;
@@ -503,18 +512,34 @@ static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
if (dom->id >= data->plat_data->dom_cnt)
goto put_dma_cookie;

+ spin_lock_irqsave(&pgtable->domain_lock, flags);
+ if (pgtable->domain_count >= data->plat_data->dom_cnt) {
+ spin_unlock_irqrestore(&pgtable->domain_lock, flags);
+ dev_err(dev, "%s, too many domain, count=%u\n",
+ __func__, pgtable->domain_count);
+ goto put_dma_cookie;
+ }
+ pgtable->domain_count++;
+ spin_unlock_irqrestore(&pgtable->domain_lock, flags);
dom->data = data;
dom->group = data->m4u_group;
+
/* Update our support page sizes bitmap */
dom->domain.pgsize_bitmap = pgtable->cfg.pgsize_bitmap;

dom->domain.geometry.aperture_start =
- pgtable->dom_region->min_iova;
+ pgtable->dom_region[dom->id].min_iova;
dom->domain.geometry.aperture_end =
- pgtable->dom_region->max_iova;
+ pgtable->dom_region[dom->id].max_iova;
dom->domain.geometry.force_aperture = true;
list_add_tail(&dom->list, &pgtable->m4u_dom_v2);

+ dev_info(dev, "%s: dom_id:%u, start:%pa, end:%pa, dom_cnt:%u\n",
+ __func__, dom->id,
+ &dom->domain.geometry.aperture_start,
+ &dom->domain.geometry.aperture_end,
+ pgtable->domain_count);
+
return &dom->domain;

put_dma_cookie:
@@ -527,9 +552,17 @@ static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
static void mtk_iommu_domain_free(struct iommu_domain *domain)
{
struct mtk_iommu_pgtable *pgtable = mtk_iommu_get_pgtable();
+ unsigned long flags;

iommu_put_dma_cookie(domain);
kfree(to_mtk_domain(domain));
+ spin_lock_irqsave(&pgtable->domain_lock, flags);
+ pgtable->domain_count--;
+ if (pgtable->domain_count > 0) {
+ spin_unlock_irqrestore(&pgtable->domain_lock, flags);
+ return;
+ }
+ spin_unlock_irqrestore(&pgtable->domain_lock, flags);
free_io_pgtable_ops(pgtable->iop);
kfree(pgtable);
}
@@ -703,6 +736,7 @@ static void mtk_iommu_get_resv_regions(struct device *dev,
{
struct mtk_iommu_data *data = dev_iommu_fwspec_get(dev)->iommu_priv;
unsigned int i, total_cnt = data->plat_data->resv_cnt;
+ u32 dom_id = mtk_iommu_get_domain_id(dev);
const struct mtk_iommu_resv_iova_region *resv_data;
struct iommu_resv_region *region;
unsigned long base = 0;
@@ -717,7 +751,7 @@ static void mtk_iommu_get_resv_regions(struct device *dev,
base = (unsigned long)resv_data[i].iova_base;
size = resv_data[i].iova_size;
}
- if (!size)
+ if (!size || resv_data[i].dom_id != dom_id)
continue;

region = iommu_alloc_resv_region(base, size, prot,
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index 10476b23adee..345c0a0c2881 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -37,6 +37,7 @@ enum mtk_iommu_plat {
};

struct mtk_iommu_resv_iova_region {
+ u32 dom_id;
dma_addr_t iova_base;
size_t iova_size;
enum iommu_resv_type type;
@@ -50,12 +51,20 @@ struct mtk_iommu_resv_iova_region {
* struct mtk_domain_data: domain configuration
* @min_iova: Start address of iova
* @max_iova: End address of iova
- * Note: one user can only belong to one domain
+ * @port_mask: User can specify mtk_iommu_domain by smi larb and port.
+ * Different mtk_iommu_domain have different iova space,
+ * port_mask is made up of larb_id and port_id.
+ * The format of larb and port can refer to mtxxxx-larb-port.h.
+ * bit[4:0] = port_id bit[11:5] = larb_id.
+ * Note: one user can only belong to one domain,
+ * the port mask is in unit of SMI larb.
*/
+#define MTK_MAX_PORT_NUM 5

struct mtk_domain_data {
dma_addr_t min_iova;
dma_addr_t max_iova;
+ u32 port_mask[MTK_MAX_PORT_NUM];
};

struct mtk_iommu_plat_data {
--
2.18.0