[PATCH v6 3/7] iommu/exynos: Simplify internal enable/disable functions

From: Marek Szyprowski
Date: Tue Nov 08 2016 - 08:31:19 EST


Remove remaining leftovers of the ref-count related code in the
__sysmmu_enable/disable functions inline __sysmmu_enable/disable_nocount
to them. Suspend/resume callbacks now checks if master device is set for
given SYSMMU controller instead of relying on the activation count.

Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
drivers/iommu/exynos-iommu.c | 104 ++++++++++++-------------------------------
1 file changed, 29 insertions(+), 75 deletions(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 4056228..f45b274 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -237,8 +237,8 @@ struct sysmmu_drvdata {
struct clk *aclk; /* SYSMMU's aclk clock */
struct clk *pclk; /* SYSMMU's pclk clock */
struct clk *clk_master; /* master's device clock */
- int activations; /* number of calls to sysmmu_enable */
spinlock_t lock; /* lock for modyfying state */
+ int active; /* current status */
struct exynos_iommu_domain *domain; /* domain we belong to */
struct list_head domain_node; /* node for domain clients list */
struct list_head owner_node; /* node for owner controllers list */
@@ -251,25 +251,6 @@ static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
return container_of(dom, struct exynos_iommu_domain, domain);
}

-static bool set_sysmmu_active(struct sysmmu_drvdata *data)
-{
- /* return true if the System MMU was not active previously
- and it needs to be initialized */
- return ++data->activations == 1;
-}
-
-static bool set_sysmmu_inactive(struct sysmmu_drvdata *data)
-{
- /* return true if the System MMU is needed to be disabled */
- BUG_ON(data->activations < 1);
- return --data->activations == 0;
-}
-
-static bool is_sysmmu_active(struct sysmmu_drvdata *data)
-{
- return data->activations > 0;
-}
-
static void sysmmu_unblock(struct sysmmu_drvdata *data)
{
writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
@@ -388,7 +369,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
unsigned short reg_status, reg_clear;
int ret = -ENOSYS;

- WARN_ON(!is_sysmmu_active(data));
+ WARN_ON(!data->active);

if (MMU_MAJ_VER(data->version) < 5) {
reg_status = REG_INT_STATUS;
@@ -434,37 +415,19 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
+static void __sysmmu_disable(struct sysmmu_drvdata *data)
{
+ unsigned long flags;
+
clk_enable(data->clk_master);

+ spin_lock_irqsave(&data->lock, flags);
writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
writel(0, data->sfrbase + REG_MMU_CFG);
-
- __sysmmu_disable_clocks(data);
-}
-
-static bool __sysmmu_disable(struct sysmmu_drvdata *data)
-{
- bool disabled;
- unsigned long flags;
-
- spin_lock_irqsave(&data->lock, flags);
-
- disabled = set_sysmmu_inactive(data);
-
- if (disabled) {
- data->pgtable = 0;
- data->domain = NULL;
-
- __sysmmu_disable_nocount(data);
-
- dev_dbg(data->sysmmu, "Disabled\n");
- }
-
+ data->active = false;
spin_unlock_irqrestore(&data->lock, flags);

- return disabled;
+ __sysmmu_disable_clocks(data);
}

static void __sysmmu_init_config(struct sysmmu_drvdata *data)
@@ -481,17 +444,19 @@ static void __sysmmu_init_config(struct sysmmu_drvdata *data)
writel(cfg, data->sfrbase + REG_MMU_CFG);
}

-static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
+static void __sysmmu_enable(struct sysmmu_drvdata *data)
{
+ unsigned long flags;
+
__sysmmu_enable_clocks(data);

+ spin_lock_irqsave(&data->lock, flags);
writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
-
__sysmmu_init_config(data);
-
__sysmmu_set_ptbase(data, data->pgtable);
-
writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
+ data->active = true;
+ spin_unlock_irqrestore(&data->lock, flags);

/*
* SYSMMU driver keeps master's clock enabled only for the short
@@ -502,37 +467,18 @@ static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
clk_disable(data->clk_master);
}

-static int __sysmmu_enable(struct sysmmu_drvdata *data, phys_addr_t pgtable,
- struct exynos_iommu_domain *domain)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&data->lock, flags);
- if (set_sysmmu_active(data)) {
- data->pgtable = pgtable;
- data->domain = domain;
- __sysmmu_enable_nocount(data);
- dev_dbg(data->sysmmu, "Enabled\n");
- }
- spin_unlock_irqrestore(&data->lock, flags);
-
- return 0;
-}
-
static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
sysmmu_iova_t iova)
{
unsigned long flags;

-
spin_lock_irqsave(&data->lock, flags);
- if (is_sysmmu_active(data) && data->version >= MAKE_MMU_VER(3, 3)) {
+ if (data->active && 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);
-
}

static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
@@ -541,7 +487,7 @@ static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
unsigned long flags;

spin_lock_irqsave(&data->lock, flags);
- if (is_sysmmu_active(data)) {
+ if (data->active) {
unsigned int num_inv = 1;

clk_enable(data->clk_master);
@@ -652,10 +598,11 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
static int exynos_sysmmu_suspend(struct device *dev)
{
struct sysmmu_drvdata *data = dev_get_drvdata(dev);
+ struct device *master = data->master;

dev_dbg(dev, "suspend\n");
- if (is_sysmmu_active(data)) {
- __sysmmu_disable_nocount(data);
+ if (master) {
+ __sysmmu_disable(data);
pm_runtime_put(dev);
}
return 0;
@@ -664,11 +611,12 @@ static int exynos_sysmmu_suspend(struct device *dev)
static int exynos_sysmmu_resume(struct device *dev)
{
struct sysmmu_drvdata *data = dev_get_drvdata(dev);
+ struct device *master = data->master;

dev_dbg(dev, "resume\n");
- if (is_sysmmu_active(data)) {
+ if (master) {
pm_runtime_get_sync(dev);
- __sysmmu_enable_nocount(data);
+ __sysmmu_enable(data);
}
return 0;
}
@@ -780,6 +728,8 @@ static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)

list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
__sysmmu_disable(data);
+ data->pgtable = 0;
+ data->domain = NULL;
data->master = NULL;
list_del_init(&data->domain_node);
}
@@ -823,6 +773,8 @@ static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
__sysmmu_disable(data);
data->master = NULL;
+ data->pgtable = 0;
+ data->domain = NULL;
list_del_init(&data->domain_node);
pm_runtime_put(data->sysmmu);
}
@@ -850,8 +802,10 @@ static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
exynos_iommu_detach_device(owner->domain, dev);

list_for_each_entry(data, &owner->controllers, owner_node) {
+ data->pgtable = pagetable;
+ data->domain = domain;
pm_runtime_get_sync(data->sysmmu);
- __sysmmu_enable(data, pagetable, domain);
+ __sysmmu_enable(data);
data->master = dev;

spin_lock_irqsave(&domain->lock, flags);
--
1.9.1