Merge tag 'omap-for-v4.8/legacy-signed' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / drivers / iommu / exynos-iommu.c

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 9893656..33dcc29 100644 (file)
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -54,6 +54,10 @@ typedef u32 sysmmu_pte_t;
 #define lv2ent_small(pent) ((*(pent) & 2) == 2)
 #define lv2ent_large(pent) ((*(pent) & 3) == 1)
 
+#ifdef CONFIG_BIG_ENDIAN
+#warning "revisit driver if we can enable big-endian ptes"
+#endif
+
 /*
  * v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces
  * v5.0 introduced support for 36bit physical address space by shifting
@@ -322,14 +326,27 @@ static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd)
        __sysmmu_tlb_invalidate(data);
 }
 
+static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data)
+{
+       BUG_ON(clk_prepare_enable(data->clk_master));
+       BUG_ON(clk_prepare_enable(data->clk));
+       BUG_ON(clk_prepare_enable(data->pclk));
+       BUG_ON(clk_prepare_enable(data->aclk));
+}
+
+static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data)
+{
+       clk_disable_unprepare(data->aclk);
+       clk_disable_unprepare(data->pclk);
+       clk_disable_unprepare(data->clk);
+       clk_disable_unprepare(data->clk_master);
+}
+
 static void __sysmmu_get_version(struct sysmmu_drvdata *data)
 {
        u32 ver;
 
-       clk_enable(data->clk_master);
-       clk_enable(data->clk);
-       clk_enable(data->pclk);
-       clk_enable(data->aclk);
+       __sysmmu_enable_clocks(data);
 
        ver = readl(data->sfrbase + REG_MMU_VERSION);
 
@@ -342,10 +359,7 @@ static void __sysmmu_get_version(struct sysmmu_drvdata *data)
        dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
                MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
 
-       clk_disable(data->aclk);
-       clk_disable(data->pclk);
-       clk_disable(data->clk);
-       clk_disable(data->clk_master);
+       __sysmmu_disable_clocks(data);
 }
 
 static void show_fault_information(struct sysmmu_drvdata *data,
@@ -427,10 +441,7 @@ static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
        writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
        writel(0, data->sfrbase + REG_MMU_CFG);
 
-       clk_disable(data->aclk);
-       clk_disable(data->pclk);
-       clk_disable(data->clk);
-       clk_disable(data->clk_master);
+       __sysmmu_disable_clocks(data);
 }
 
 static bool __sysmmu_disable(struct sysmmu_drvdata *data)
@@ -475,10 +486,7 @@ static void __sysmmu_init_config(struct sysmmu_drvdata *data)
 
 static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
 {
-       clk_enable(data->clk_master);
-       clk_enable(data->clk);
-       clk_enable(data->pclk);
-       clk_enable(data->aclk);
+       __sysmmu_enable_clocks(data);
 
        writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
 
@@ -488,6 +496,12 @@ static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
 
        writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
 
+       /*
+        * SYSMMU driver keeps master's clock enabled only for the short
+        * time, while accessing the registers. For performing address
+        * translation during DMA transaction it relies on the client
+        * driver to enable it.
+        */
        clk_disable(data->clk_master);
 }
 
@@ -524,16 +538,15 @@ static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
 {
        unsigned long flags;
 
-       clk_enable(data->clk_master);
 
        spin_lock_irqsave(&data->lock, flags);
-       if (is_sysmmu_active(data)) {
-               if (data->version >= MAKE_MMU_VER(3, 3))
-                       __sysmmu_tlb_invalidate_entry(data, iova, 1);
+       if (is_sysmmu_active(data) && data->version >= MAKE_MMU_VER(3, 3)) {
+               clk_enable(data->clk_master);
+               __sysmmu_tlb_invalidate_entry(data, iova, 1);
+               clk_disable(data->clk_master);
        }
        spin_unlock_irqrestore(&data->lock, flags);
 
-       clk_disable(data->clk_master);
 }
 
 static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
@@ -572,6 +585,8 @@ static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
        spin_unlock_irqrestore(&data->lock, flags);
 }
 
+static struct iommu_ops exynos_iommu_ops;
+
 static int __init exynos_sysmmu_probe(struct platform_device *pdev)
 {
        int irq, ret;
@@ -606,27 +621,18 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
                data->clk = NULL;
        else if (IS_ERR(data->clk))
                return PTR_ERR(data->clk);
-       ret = clk_prepare(data->clk);
-       if (ret)
-               return ret;
 
        data->aclk = devm_clk_get(dev, "aclk");
        if (PTR_ERR(data->aclk) == -ENOENT)
                data->aclk = NULL;
        else if (IS_ERR(data->aclk))
                return PTR_ERR(data->aclk);
-       ret = clk_prepare(data->aclk);
-       if (ret)
-               return ret;
 
        data->pclk = devm_clk_get(dev, "pclk");
        if (PTR_ERR(data->pclk) == -ENOENT)
                data->pclk = NULL;
        else if (IS_ERR(data->pclk))
                return PTR_ERR(data->pclk);
-       ret = clk_prepare(data->pclk);
-       if (ret)
-               return ret;
 
        if (!data->clk && (!data->aclk || !data->pclk)) {
                dev_err(dev, "Failed to get device clock(s)!\n");
@@ -638,9 +644,6 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
                data->clk_master = NULL;
        else if (IS_ERR(data->clk_master))
                return PTR_ERR(data->clk_master);
-       ret = clk_prepare(data->clk_master);
-       if (ret)
-               return ret;
 
        data->sysmmu = dev;
        spin_lock_init(&data->lock);
@@ -657,6 +660,8 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
 
        pm_runtime_enable(dev);
 
+       of_iommu_set_ops(dev->of_node, &exynos_iommu_ops);
+
        return 0;
 }
 
@@ -709,7 +714,7 @@ static inline void update_pte(sysmmu_pte_t *ent, sysmmu_pte_t val)
 {
        dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent),
                                DMA_TO_DEVICE);
-       *ent = val;
+       *ent = cpu_to_le32(val);
        dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent),
                                   DMA_TO_DEVICE);
 }
@@ -1350,7 +1355,6 @@ static int __init exynos_iommu_of_setup(struct device_node *np)
        if (!dma_dev)
                dma_dev = &pdev->dev;
 
-       of_iommu_set_ops(np, &exynos_iommu_ops);
        return 0;
 }