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path: root/drivers/clk/renesas/clk-mstp.c
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Diffstat (limited to 'drivers/clk/renesas/clk-mstp.c')
-rw-r--r--drivers/clk/renesas/clk-mstp.c44
1 files changed, 36 insertions, 8 deletions
diff --git a/drivers/clk/renesas/clk-mstp.c b/drivers/clk/renesas/clk-mstp.c
index 9375777776d9..4067216bf31f 100644
--- a/drivers/clk/renesas/clk-mstp.c
+++ b/drivers/clk/renesas/clk-mstp.c
@@ -37,12 +37,14 @@
* @smstpcr: module stop control register
* @mstpsr: module stop status register (optional)
* @lock: protects writes to SMSTPCR
+ * @width_8bit: registers are 8-bit, not 32-bit
*/
struct mstp_clock_group {
struct clk_onecell_data data;
void __iomem *smstpcr;
void __iomem *mstpsr;
spinlock_t lock;
+ bool width_8bit;
};
/**
@@ -59,6 +61,18 @@ struct mstp_clock {
#define to_mstp_clock(_hw) container_of(_hw, struct mstp_clock, hw)
+static inline u32 cpg_mstp_read(struct mstp_clock_group *group,
+ u32 __iomem *reg)
+{
+ return group->width_8bit ? readb(reg) : clk_readl(reg);
+}
+
+static inline void cpg_mstp_write(struct mstp_clock_group *group, u32 val,
+ u32 __iomem *reg)
+{
+ group->width_8bit ? writeb(val, reg) : clk_writel(val, reg);
+}
+
static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
{
struct mstp_clock *clock = to_mstp_clock(hw);
@@ -70,12 +84,18 @@ static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
spin_lock_irqsave(&group->lock, flags);
- value = clk_readl(group->smstpcr);
+ value = cpg_mstp_read(group, group->smstpcr);
if (enable)
value &= ~bitmask;
else
value |= bitmask;
- clk_writel(value, group->smstpcr);
+ cpg_mstp_write(group, value, group->smstpcr);
+
+ if (!group->mstpsr) {
+ /* dummy read to ensure write has completed */
+ cpg_mstp_read(group, group->smstpcr);
+ barrier_data(group->smstpcr);
+ }
spin_unlock_irqrestore(&group->lock, flags);
@@ -83,7 +103,7 @@ static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
return 0;
for (i = 1000; i > 0; --i) {
- if (!(clk_readl(group->mstpsr) & bitmask))
+ if (!(cpg_mstp_read(group, group->mstpsr) & bitmask))
break;
cpu_relax();
}
@@ -114,9 +134,9 @@ static int cpg_mstp_clock_is_enabled(struct clk_hw *hw)
u32 value;
if (group->mstpsr)
- value = clk_readl(group->mstpsr);
+ value = cpg_mstp_read(group, group->mstpsr);
else
- value = clk_readl(group->smstpcr);
+ value = cpg_mstp_read(group, group->smstpcr);
return !(value & BIT(clock->bit_index));
}
@@ -127,9 +147,9 @@ static const struct clk_ops cpg_mstp_clock_ops = {
.is_enabled = cpg_mstp_clock_is_enabled,
};
-static struct clk * __init
-cpg_mstp_clock_register(const char *name, const char *parent_name,
- unsigned int index, struct mstp_clock_group *group)
+static struct clk * __init cpg_mstp_clock_register(const char *name,
+ const char *parent_name, unsigned int index,
+ struct mstp_clock_group *group)
{
struct clk_init_data init;
struct mstp_clock *clock;
@@ -144,6 +164,11 @@ cpg_mstp_clock_register(const char *name, const char *parent_name,
init.name = name;
init.ops = &cpg_mstp_clock_ops;
init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT;
+ /* INTC-SYS is the module clock of the GIC, and must not be disabled */
+ if (!strcmp(name, "intc-sys")) {
+ pr_debug("MSTP %s setting CLK_IS_CRITICAL\n", name);
+ init.flags |= CLK_IS_CRITICAL;
+ }
init.parent_names = &parent_name;
init.num_parents = 1;
@@ -188,6 +213,9 @@ static void __init cpg_mstp_clocks_init(struct device_node *np)
return;
}
+ if (of_device_is_compatible(np, "renesas,r7s72100-mstp-clocks"))
+ group->width_8bit = true;
+
for (i = 0; i < MSTP_MAX_CLOCKS; ++i)
clks[i] = ERR_PTR(-ENOENT);
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