Re: [PATCH v11 08/27] iommu/exynos: always use a single clock descriptor
From: Tomasz Figa
Date: Fri Mar 14 2014 - 09:07:48 EST
Hi KyongHo,
On 14.03.2014 06:05, Cho KyongHo wrote:
System MMU driver is changed to control only a single instance of
System MMU at a time. Since a single instance of System MMU has only
a single clock descriptor for its clock gating, there is no need to
obtain two or more clock descriptors.
This patch does much more than just making the driver use a single clock
descriptor. Please update the subject and description accordingly.
Signed-off-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
---
drivers/iommu/exynos-iommu.c | 223 ++++++++++++++----------------------------
1 file changed, 72 insertions(+), 151 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 8dc7031..a4499b2 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -171,9 +171,8 @@ struct sysmmu_drvdata {
struct device *sysmmu; /* System MMU's device descriptor */
struct device *dev; /* Owner of system MMU */
char *dbgname;
- int nsfrs;
- void __iomem **sfrbases;
- struct clk *clk[2];
+ void __iomem *sfrbase;
+ struct clk *clk;
int activations;
rwlock_t lock;
struct iommu_domain *domain;
@@ -294,56 +293,39 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
{
/* SYSMMU is in blocked when interrupt occurred. */
struct sysmmu_drvdata *data = dev_id;
- struct resource *irqres;
- struct platform_device *pdev;
enum exynos_sysmmu_inttype itype;
unsigned long addr = -1;
-
- int i, ret = -ENOSYS;
+ int ret = -ENOSYS;
read_lock(&data->lock);
WARN_ON(!is_sysmmu_active(data));
- pdev = to_platform_device(data->sysmmu);
- for (i = 0; i < (pdev->num_resources / 2); i++) {
- irqres = platform_get_resource(pdev, IORESOURCE_IRQ, i);
- if (irqres && ((int)irqres->start == irq))
- break;
- }
-
- if (i == pdev->num_resources) {
+ itype = (enum exynos_sysmmu_inttype)
+ __ffs(__raw_readl(data->sfrbase + REG_INT_STATUS));
+ if (WARN_ON(!((itype >= 0) && (itype < SYSMMU_FAULT_UNKNOWN))))
itype = SYSMMU_FAULT_UNKNOWN;
- } else {
- itype = (enum exynos_sysmmu_inttype)
- __ffs(__raw_readl(data->sfrbases[i] + REG_INT_STATUS));
- if (WARN_ON(!((itype >= 0) && (itype < SYSMMU_FAULT_UNKNOWN))))
- itype = SYSMMU_FAULT_UNKNOWN;
- else
- addr = __raw_readl(
- data->sfrbases[i] + fault_reg_offset[itype]);
- }
+ else
+ addr = __raw_readl(data->sfrbase + fault_reg_offset[itype]);
if (data->domain)
- ret = report_iommu_fault(data->domain, data->dev,
- addr, itype);
+ ret = report_iommu_fault(data->domain, data->dev, addr, itype);
if ((ret == -ENOSYS) && data->fault_handler) {
unsigned long base = data->pgtable;
if (itype != SYSMMU_FAULT_UNKNOWN)
- base = __raw_readl(
- data->sfrbases[i] + REG_PT_BASE_ADDR);
+ base = __raw_readl(data->sfrbase + REG_PT_BASE_ADDR);
ret = data->fault_handler(itype, base, addr);
}
if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
- __raw_writel(1 << itype, data->sfrbases[i] + REG_INT_CLEAR);
+ __raw_writel(1 << itype, data->sfrbase + REG_INT_CLEAR);
else
dev_dbg(data->sysmmu, "(%s) %s is not handled.\n",
data->dbgname, sysmmu_fault_name[itype]);
if (itype != SYSMMU_FAULT_UNKNOWN)
- sysmmu_unblock(data->sfrbases[i]);
+ sysmmu_unblock(data->sfrbase);
read_unlock(&data->lock);
@@ -354,20 +336,16 @@ static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
{
unsigned long flags;
bool disabled = false;
- int i;
write_lock_irqsave(&data->lock, flags);
if (!set_sysmmu_inactive(data))
goto finish;
- for (i = 0; i < data->nsfrs; i++)
- __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
+ __raw_writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
- if (data->clk[1])
- clk_disable(data->clk[1]);
- if (data->clk[0])
- clk_disable(data->clk[0]);
+ if (data->clk)
I know this is already in the driver, but checking (struct clk *) for
NULL is incorrect. NULL is a valid pointer for dummy clocks on platforms
which do not provide particular clocks, to make this transparent to
drivers. IS_ERR() should be used to check whether a clock pointer is valid.
This patch is changing all the clock code anyway, so this change could
be squashed into it to fix this.
+ clk_disable(data->clk);
disabled = true;
data->pgtable = 0;
@@ -393,7 +371,7 @@ finish:
static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
unsigned long pgtable, struct iommu_domain *domain)
{
- int i, ret = 0;
+ int ret = 0;
unsigned long flags;
write_lock_irqsave(&data->lock, flags);
@@ -410,17 +388,14 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
goto finish;
}
- if (data->clk[0])
- clk_enable(data->clk[0]);
- if (data->clk[1])
- clk_enable(data->clk[1]);
+ if (data->clk)
+ clk_enable(data->clk);
data->pgtable = pgtable;
- for (i = 0; i < data->nsfrs; i++) {
- __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
- __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
- }
+ __sysmmu_set_ptbase(data->sfrbase, pgtable);
+
+ __raw_writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
data->domain = domain;
@@ -477,28 +452,26 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova,
read_lock_irqsave(&data->lock, flags);
if (is_sysmmu_active(data)) {
- int i;
- for (i = 0; i < data->nsfrs; i++) {
- unsigned int maj;
- unsigned int num_inv = 1;
- maj = __raw_readl(data->sfrbases[i] + REG_MMU_VERSION);
- /*
- * L2TLB invalidation required
- * 4KB page: 1 invalidation
- * 64KB page: 16 invalidation
- * 1MB page: 64 invalidation
- * because it is set-associative TLB
- * with 8-way and 64 sets.
- * 1MB page can be cached in one of all sets.
- * 64KB page can be one of 16 consecutive sets.
- */
- if ((maj >> 28) == 2) /* major version number */
- num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
- if (sysmmu_block(data->sfrbases[i])) {
- __sysmmu_tlb_invalidate_entry(
- data->sfrbases[i], iova, num_inv);
- sysmmu_unblock(data->sfrbases[i]);
- }
+ 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
+ * because it is set-associative TLB
+ * with 8-way and 64 sets.
+ * 1MB page can be cached in one of all sets.
+ * 64KB page can be one of 16 consecutive sets.
+ */
+ if ((maj >> 28) == 2) /* major version number */
+ num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
+
+ if (sysmmu_block(data->sfrbase)) {
+ __sysmmu_tlb_invalidate_entry(data->sfrbase, iova,
+ num_inv);
+ sysmmu_unblock(data->sfrbase);
}
} else {
dev_dbg(data->sysmmu,
@@ -517,12 +490,9 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev)
read_lock_irqsave(&data->lock, flags);
if (is_sysmmu_active(data)) {
- int i;
- for (i = 0; i < data->nsfrs; i++) {
- if (sysmmu_block(data->sfrbases[i])) {
- __sysmmu_tlb_invalidate(data->sfrbases[i]);
- sysmmu_unblock(data->sfrbases[i]);
- }
+ if (sysmmu_block(data->sfrbase)) {
+ __sysmmu_tlb_invalidate(data->sfrbase);
+ sysmmu_unblock(data->sfrbase);
}
} else {
dev_dbg(data->sysmmu,
@@ -535,11 +505,10 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev)
static int exynos_sysmmu_probe(struct platform_device *pdev)
{
- int i, ret;
- struct device *dev;
+ int ret;
+ struct device *dev = &pdev->dev;
struct sysmmu_drvdata *data;
-
- dev = &pdev->dev;
+ struct resource *res;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data) {
@@ -548,82 +517,39 @@ static int exynos_sysmmu_probe(struct platform_device *pdev)
goto err_alloc;
}
- ret = dev_set_drvdata(dev, data);
- if (ret) {
- dev_dbg(dev, "Unabled to initialize driver data\n");
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_dbg(dev, "Unable to find IOMEM region\n");
+ ret = -ENOENT;
goto err_init;
}
- data->nsfrs = pdev->num_resources / 2;
- data->sfrbases = kmalloc(sizeof(*data->sfrbases) * data->nsfrs,
- GFP_KERNEL);
- if (data->sfrbases == NULL) {
- dev_dbg(dev, "Not enough memory\n");
- ret = -ENOMEM;
- goto err_init;
+ data->sfrbase = ioremap(res->start, resource_size(res));
+ if (!data->sfrbase) {
+ dev_dbg(dev, "Unable to map IOMEM @ PA:%#x\n", res->start);
+ ret = -ENOENT;
+ goto err_res;
}
- for (i = 0; i < data->nsfrs; i++) {
- struct resource *res;
- res = platform_get_resource(pdev, IORESOURCE_MEM, i);
- if (!res) {
- dev_dbg(dev, "Unable to find IOMEM region\n");
- ret = -ENOENT;
- goto err_res;
- }
-
- data->sfrbases[i] = ioremap(res->start, resource_size(res));
- if (!data->sfrbases[i]) {
- dev_dbg(dev, "Unable to map IOMEM @ PA:%#x\n",
- res->start);
- ret = -ENOENT;
- goto err_res;
- }
+ ret = platform_get_irq(pdev, 0);
+ if (ret <= 0) {
+ dev_dbg(dev, "Unable to find IRQ resource\n");
+ goto err_irq;
}
- for (i = 0; i < data->nsfrs; i++) {
- ret = platform_get_irq(pdev, i);
- if (ret <= 0) {
- dev_dbg(dev, "Unable to find IRQ resource\n");
- goto err_irq;
- }
-
- ret = request_irq(ret, exynos_sysmmu_irq, 0,
- dev_name(dev), data);
- if (ret) {
- dev_dbg(dev, "Unabled to register interrupt handler\n");
- goto err_irq;
- }
+ ret = request_irq(ret, exynos_sysmmu_irq, 0,
+ dev_name(dev), data);
+ if (ret) {
+ dev_dbg(dev, "Unabled to register interrupt handler\n");
+ goto err_irq;
}
if (dev_get_platdata(dev)) {
- char *deli, *beg;
- struct sysmmu_platform_data *platdata = dev_get_platdata(dev);
-
- beg = platdata->clockname;
-
- for (deli = beg; (*deli != '\0') && (*deli != ','); deli++)
- /* NOTHING */;
-
- if (*deli == '\0')
- deli = NULL;
- else
- *deli = '\0';
-
- data->clk[0] = clk_get(dev, beg);
- if (IS_ERR(data->clk[0])) {
- data->clk[0] = NULL;
+ data->clk = clk_get(dev, "sysmmu");
+ if (IS_ERR(data->clk)) {
+ data->clk = NULL;
This is incorrect. IS_ERR() should be used through the driver and the
error value here should not be replaced with NULL.
--
Best regards,
Tomasz
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