This patch gates clocks of master H/W as well as clocks of System MMU
if master clocks are specified.
Some Exynos SoCs (i.e. GScalers in Exynos5250) have dependencies in
the gating clocks of master H/W and its System MMU. If a H/W is the
case, accessing control registers of System MMU is prohibited unless
both of the gating clocks of System MMU and its master H/W.
CC: Tomasz Figa <t.figa@xxxxxxxxxxx>
Signed-off-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
---
drivers/iommu/exynos-iommu.c | 75 +++++++++++++++++++++++++++++++----------
1 files changed, 56 insertions(+), 19 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index cf30519..75efdb81 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -80,6 +80,8 @@
#define CTRL_BLOCK 0x7
#define CTRL_DISABLE 0x0
+#define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
+
#define REG_MMU_CTRL 0x000
#define REG_MMU_CFG 0x004
#define REG_MMU_STATUS 0x008
@@ -96,6 +98,9 @@
#define REG_MMU_VERSION 0x034
+#define MMU_MAJ_VER(reg) (reg >> 28)
+#define MMU_MIN_VER(reg) ((reg >> 21) & 0x7F)
+
#define REG_PB0_SADDR 0x04C
#define REG_PB0_EADDR 0x050
#define REG_PB1_SADDR 0x054
@@ -173,6 +178,7 @@ struct sysmmu_drvdata {
struct device *dev; /* Owner of system MMU */
void __iomem *sfrbase;
struct clk *clk;
+ struct clk *clk_master;
int activations;
rwlock_t lock;
struct iommu_domain *domain;
@@ -199,6 +205,22 @@ static bool is_sysmmu_active(struct sysmmu_drvdata *data)
return data->activations > 0;
}
+static unsigned int __sysmmu_version(struct sysmmu_drvdata *data,
+ unsigned int *minor)
+{
+ unsigned long major;
+
+ major = readl(data->sfrbase + REG_MMU_VERSION);
+
+ if (minor)
+ *minor = MMU_MIN_VER(major);
+
+ if (MMU_MAJ_VER(major) > 3)
+ return 1;
+
+ return MMU_MAJ_VER(major);
+}
+
static void sysmmu_unblock(void __iomem *sfrbase)
{
__raw_writel(CTRL_ENABLE, sfrbase + REG_MMU_CTRL);
@@ -245,13 +267,6 @@ static void __sysmmu_set_ptbase(void __iomem *sfrbase,
__sysmmu_tlb_invalidate(sfrbase);
}
-static void __sysmmu_set_prefbuf(void __iomem *sfrbase, unsigned long base,
- unsigned long size, int idx)
-{
- __raw_writel(base, sfrbase + REG_PB0_SADDR + idx * 8);
- __raw_writel(size - 1 + base, sfrbase + REG_PB0_EADDR + idx * 8);
-}
-
static void __set_fault_handler(struct sysmmu_drvdata *data,
sysmmu_fault_handler_t handler)
{
@@ -308,6 +323,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
WARN_ON(!is_sysmmu_active(data));
+ clk_enable(data->clk_master);
itype = (enum exynos_sysmmu_inttype)
__ffs(__raw_readl(data->sfrbase + REG_INT_STATUS));
if (WARN_ON(!((itype >= 0) && (itype < SYSMMU_FAULT_UNKNOWN))))
@@ -334,6 +350,8 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
if (itype != SYSMMU_FAULT_UNKNOWN)
sysmmu_unblock(data->sfrbase);
+ clk_disable(data->clk_master);
+
read_unlock(&data->lock);
return IRQ_HANDLED;
@@ -349,10 +367,13 @@ static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
if (!set_sysmmu_inactive(data))
goto finish;
+ clk_enable(data->clk_master);
+
__raw_writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
- if (data->clk)
- clk_disable(data->clk);
+ clk_disable(data->clk_master);
+
+ clk_disable(data->clk);
disabled = true;
data->pgtable = 0;
@@ -380,6 +401,7 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
{
int ret = 0;
unsigned long flags;
+ unsigned int min;
write_lock_irqsave(&data->lock, flags);
@@ -395,22 +417,24 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
goto finish;
}
- if (data->clk)
- clk_enable(data->clk);
data->pgtable = pgtable;
+ clk_enable(data->clk);
+ clk_enable(data->clk_master);
+
__sysmmu_set_ptbase(data->sfrbase, pgtable);
- if ((readl(data->sfrbase + REG_MMU_VERSION) >> 28) == 3) {
- /* System MMU version is 3.x */
- __raw_writel((1 << 12) | (2 << 28), data->sfrbase + REG_MMU_CFG);
- __sysmmu_set_prefbuf(data->sfrbase, 0, -1, 0);
- __sysmmu_set_prefbuf(data->sfrbase, 0, -1, 1);
+ if ((__sysmmu_version(data, &min) == 3) && (min > 1)) {
+ unsigned long cfg;
+ cfg = __raw_readl(data->sfrbase + REG_MMU_CFG);
+ __raw_writel(cfg | CFG_FLPDCACHE, data->sfrbase + REG_MMU_CFG);
}
__raw_writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
+ clk_disable(data->clk_master);
+
data->domain = domain;
dev_dbg(data->sysmmu, "Enabled\n");
@@ -465,23 +489,23 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova,
read_lock_irqsave(&data->lock, flags);
if (is_sysmmu_active(data)) {
- unsigned int maj;
unsigned int num_inv = 1;
- maj = __raw_readl(data->sfrbase + REG_MMU_VERSION);
/*
* L2TLB invalidation required
* 4KB page: 1 invalidation
* 64KB page: 16 invalidation
* 1MB page: 64 invalidation
*/
- if ((maj >> 28) == 2) /* major version number */
+ if (__sysmmu_version(data, NULL) == 2)
num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
+ clk_enable(data->clk_master);
if (sysmmu_block(data->sfrbase)) {
__sysmmu_tlb_invalidate_entry(data->sfrbase, iova,
num_inv);
sysmmu_unblock(data->sfrbase);
}
+ clk_disable(data->clk_master);
} else {
dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
}
@@ -497,10 +521,12 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev)
read_lock_irqsave(&data->lock, flags);
if (is_sysmmu_active(data)) {
+ clk_enable(data->clk_master);
if (sysmmu_block(data->sfrbase)) {
__sysmmu_tlb_invalidate(data->sfrbase);
sysmmu_unblock(data->sfrbase);
}
+ clk_disable(data->clk_master);
} else {
dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
}
@@ -554,6 +580,17 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
return ret;
}
+ data->clk_master = devm_clk_get(dev, "master");
+ if (IS_ERR(data->clk_master))
+ data->clk_master = NULL;
+
+ ret = clk_prepare(data->clk_master);
+ if (ret) {
+ clk_unprepare(data->clk);
+ dev_err(dev, "Failed to prepare master's clk\n");
+ return ret;
+ }
+
data->sysmmu = dev;
rwlock_init(&data->lock);
INIT_LIST_HEAD(&data->node);
--
1.7.2.5
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
