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path: root/drivers/clk/shmobile/clk-div6.c
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Diffstat (limited to 'drivers/clk/shmobile/clk-div6.c')
-rw-r--r--drivers/clk/shmobile/clk-div6.c113
1 files changed, 101 insertions, 12 deletions
diff --git a/drivers/clk/shmobile/clk-div6.c b/drivers/clk/shmobile/clk-div6.c
index f065f694cb65..639241e31e03 100644
--- a/drivers/clk/shmobile/clk-div6.c
+++ b/drivers/clk/shmobile/clk-div6.c
@@ -32,6 +32,9 @@ struct div6_clock {
struct clk_hw hw;
void __iomem *reg;
unsigned int div;
+ u32 src_shift;
+ u32 src_width;
+ u8 *parents;
};
#define to_div6_clock(_hw) container_of(_hw, struct div6_clock, hw)
@@ -39,8 +42,11 @@ struct div6_clock {
static int cpg_div6_clock_enable(struct clk_hw *hw)
{
struct div6_clock *clock = to_div6_clock(hw);
+ u32 val;
- clk_writel(CPG_DIV6_DIV(clock->div - 1), clock->reg);
+ val = (clk_readl(clock->reg) & ~(CPG_DIV6_DIV_MASK | CPG_DIV6_CKSTP))
+ | CPG_DIV6_DIV(clock->div - 1);
+ clk_writel(val, clock->reg);
return 0;
}
@@ -52,7 +58,7 @@ static void cpg_div6_clock_disable(struct clk_hw *hw)
/* DIV6 clocks require the divisor field to be non-zero when stopping
* the clock.
*/
- clk_writel(CPG_DIV6_CKSTP | CPG_DIV6_DIV(CPG_DIV6_DIV_MASK),
+ clk_writel(clk_readl(clock->reg) | CPG_DIV6_CKSTP | CPG_DIV6_DIV_MASK,
clock->reg);
}
@@ -94,12 +100,53 @@ static int cpg_div6_clock_set_rate(struct clk_hw *hw, unsigned long rate,
{
struct div6_clock *clock = to_div6_clock(hw);
unsigned int div = cpg_div6_clock_calc_div(rate, parent_rate);
+ u32 val;
clock->div = div;
+ val = clk_readl(clock->reg) & ~CPG_DIV6_DIV_MASK;
/* Only program the new divisor if the clock isn't stopped. */
- if (!(clk_readl(clock->reg) & CPG_DIV6_CKSTP))
- clk_writel(CPG_DIV6_DIV(clock->div - 1), clock->reg);
+ if (!(val & CPG_DIV6_CKSTP))
+ clk_writel(val | CPG_DIV6_DIV(clock->div - 1), clock->reg);
+
+ return 0;
+}
+
+static u8 cpg_div6_clock_get_parent(struct clk_hw *hw)
+{
+ struct div6_clock *clock = to_div6_clock(hw);
+ unsigned int i;
+ u8 hw_index;
+
+ if (clock->src_width == 0)
+ return 0;
+
+ hw_index = (clk_readl(clock->reg) >> clock->src_shift) &
+ (BIT(clock->src_width) - 1);
+ for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
+ if (clock->parents[i] == hw_index)
+ return i;
+ }
+
+ pr_err("%s: %s DIV6 clock set to invalid parent %u\n",
+ __func__, __clk_get_name(hw->clk), hw_index);
+ return 0;
+}
+
+static int cpg_div6_clock_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct div6_clock *clock = to_div6_clock(hw);
+ u8 hw_index;
+ u32 mask;
+
+ if (index >= __clk_get_num_parents(hw->clk))
+ return -EINVAL;
+
+ mask = ~((BIT(clock->src_width) - 1) << clock->src_shift);
+ hw_index = clock->parents[index];
+
+ clk_writel((clk_readl(clock->reg) & mask) |
+ (hw_index << clock->src_shift), clock->reg);
return 0;
}
@@ -108,6 +155,8 @@ static const struct clk_ops cpg_div6_clock_ops = {
.enable = cpg_div6_clock_enable,
.disable = cpg_div6_clock_disable,
.is_enabled = cpg_div6_clock_is_enabled,
+ .get_parent = cpg_div6_clock_get_parent,
+ .set_parent = cpg_div6_clock_set_parent,
.recalc_rate = cpg_div6_clock_recalc_rate,
.round_rate = cpg_div6_clock_round_rate,
.set_rate = cpg_div6_clock_set_rate,
@@ -115,20 +164,33 @@ static const struct clk_ops cpg_div6_clock_ops = {
static void __init cpg_div6_clock_init(struct device_node *np)
{
+ unsigned int num_parents, valid_parents;
+ const char **parent_names;
struct clk_init_data init;
struct div6_clock *clock;
- const char *parent_name;
const char *name;
struct clk *clk;
+ unsigned int i;
int ret;
clock = kzalloc(sizeof(*clock), GFP_KERNEL);
- if (!clock) {
- pr_err("%s: failed to allocate %s DIV6 clock\n",
+ if (!clock)
+ return;
+
+ num_parents = of_clk_get_parent_count(np);
+ if (num_parents < 1) {
+ pr_err("%s: no parent found for %s DIV6 clock\n",
__func__, np->name);
return;
}
+ clock->parents = kmalloc_array(num_parents, sizeof(*clock->parents),
+ GFP_KERNEL);
+ parent_names = kmalloc_array(num_parents, sizeof(*parent_names),
+ GFP_KERNEL);
+ if (!parent_names)
+ return;
+
/* Remap the clock register and read the divisor. Disabling the
* clock overwrites the divisor, so we need to cache its value for the
* enable operation.
@@ -150,9 +212,34 @@ static void __init cpg_div6_clock_init(struct device_node *np)
goto error;
}
- parent_name = of_clk_get_parent_name(np, 0);
- if (parent_name == NULL) {
- pr_err("%s: failed to get %s DIV6 clock parent name\n",
+
+ for (i = 0, valid_parents = 0; i < num_parents; i++) {
+ const char *name = of_clk_get_parent_name(np, i);
+
+ if (name) {
+ parent_names[valid_parents] = name;
+ clock->parents[valid_parents] = i;
+ valid_parents++;
+ }
+ }
+
+ switch (num_parents) {
+ case 1:
+ /* fixed parent clock */
+ clock->src_shift = clock->src_width = 0;
+ break;
+ case 4:
+ /* clock with EXSRC bits 6-7 */
+ clock->src_shift = 6;
+ clock->src_width = 2;
+ break;
+ case 8:
+ /* VCLK with EXSRC bits 12-14 */
+ clock->src_shift = 12;
+ clock->src_width = 3;
+ break;
+ default:
+ pr_err("%s: invalid number of parents for DIV6 clock %s\n",
__func__, np->name);
goto error;
}
@@ -161,8 +248,8 @@ static void __init cpg_div6_clock_init(struct device_node *np)
init.name = name;
init.ops = &cpg_div6_clock_ops;
init.flags = CLK_IS_BASIC;
- init.parent_names = &parent_name;
- init.num_parents = 1;
+ init.parent_names = parent_names;
+ init.num_parents = valid_parents;
clock->hw.init = &init;
@@ -175,11 +262,13 @@ static void __init cpg_div6_clock_init(struct device_node *np)
of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ kfree(parent_names);
return;
error:
if (clock->reg)
iounmap(clock->reg);
+ kfree(parent_names);
kfree(clock);
}
CLK_OF_DECLARE(cpg_div6_clk, "renesas,cpg-div6-clock", cpg_div6_clock_init);