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authorTero Kristo <t-kristo@ti.com>2014-02-24 16:06:34 +0200
committerTero Kristo <t-kristo@ti.com>2014-05-28 12:30:02 +0300
commit4d008589e271e28eae728eef7f5fb1f658f12b9f (patch)
tree8b30eee15659aa978c5b452b65647662cc90c8c3 /drivers/clk/ti
parentaa76fcf473f6bfa839f37f77b6fdb71f0fb88d8f (diff)
CLK: TI: APLL: add support for omap2 aplls
This patch adds support for omap2 type aplls, which have gating and autoidle functionality. Signed-off-by: Tero Kristo <t-kristo@ti.com>
Diffstat (limited to 'drivers/clk/ti')
-rw-r--r--drivers/clk/ti/apll.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/clk/ti/apll.c b/drivers/clk/ti/apll.c
index b986f61f5a77..5428c9c547cd 100644
--- a/drivers/clk/ti/apll.c
+++ b/drivers/clk/ti/apll.c
@@ -221,3 +221,184 @@ cleanup:
kfree(init);
}
CLK_OF_DECLARE(dra7_apll_clock, "ti,dra7-apll-clock", of_dra7_apll_setup);
+
+#define OMAP2_EN_APLL_LOCKED 0x3
+#define OMAP2_EN_APLL_STOPPED 0x0
+
+static int omap2_apll_is_enabled(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ad->enable_mask;
+
+ v >>= __ffs(ad->enable_mask);
+
+ return v == OMAP2_EN_APLL_LOCKED ? 1 : 0;
+}
+
+static unsigned long omap2_apll_recalc(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+
+ if (omap2_apll_is_enabled(hw))
+ return clk->fixed_rate;
+
+ return 0;
+}
+
+static int omap2_apll_enable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+ int i = 0;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ~ad->enable_mask;
+ v |= OMAP2_EN_APLL_LOCKED << __ffs(ad->enable_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+
+ while (1) {
+ v = ti_clk_ll_ops->clk_readl(ad->idlest_reg);
+ if (v & ad->idlest_mask)
+ break;
+ if (i > MAX_APLL_WAIT_TRIES)
+ break;
+ i++;
+ udelay(1);
+ }
+
+ if (i == MAX_APLL_WAIT_TRIES) {
+ pr_warn("%s failed to transition to locked\n",
+ __clk_get_name(clk->hw.clk));
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static void omap2_apll_disable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ~ad->enable_mask;
+ v |= OMAP2_EN_APLL_STOPPED << __ffs(ad->enable_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+}
+
+static struct clk_ops omap2_apll_ops = {
+ .enable = &omap2_apll_enable,
+ .disable = &omap2_apll_disable,
+ .is_enabled = &omap2_apll_is_enabled,
+ .recalc_rate = &omap2_apll_recalc,
+};
+
+static void omap2_apll_set_autoidle(struct clk_hw_omap *clk, u32 val)
+{
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(ad->autoidle_reg);
+ v &= ~ad->autoidle_mask;
+ v |= val << __ffs(ad->autoidle_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+}
+
+#define OMAP2_APLL_AUTOIDLE_LOW_POWER_STOP 0x3
+#define OMAP2_APLL_AUTOIDLE_DISABLE 0x0
+
+static void omap2_apll_allow_idle(struct clk_hw_omap *clk)
+{
+ omap2_apll_set_autoidle(clk, OMAP2_APLL_AUTOIDLE_LOW_POWER_STOP);
+}
+
+static void omap2_apll_deny_idle(struct clk_hw_omap *clk)
+{
+ omap2_apll_set_autoidle(clk, OMAP2_APLL_AUTOIDLE_DISABLE);
+}
+
+static struct clk_hw_omap_ops omap2_apll_hwops = {
+ .allow_idle = &omap2_apll_allow_idle,
+ .deny_idle = &omap2_apll_deny_idle,
+};
+
+static void __init of_omap2_apll_setup(struct device_node *node)
+{
+ struct dpll_data *ad = NULL;
+ struct clk_hw_omap *clk_hw = NULL;
+ struct clk_init_data *init = NULL;
+ struct clk *clk;
+ const char *parent_name;
+ u32 val;
+
+ ad = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+ clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+ init = kzalloc(sizeof(*init), GFP_KERNEL);
+
+ if (!ad || !clk_hw || !init)
+ goto cleanup;
+
+ clk_hw->dpll_data = ad;
+ clk_hw->hw.init = init;
+ init->ops = &omap2_apll_ops;
+ init->name = node->name;
+ clk_hw->ops = &omap2_apll_hwops;
+
+ init->num_parents = of_clk_get_parent_count(node);
+ if (init->num_parents != 1) {
+ pr_err("%s must have one parent\n", node->name);
+ goto cleanup;
+ }
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ init->parent_names = &parent_name;
+
+ if (of_property_read_u32(node, "ti,clock-frequency", &val)) {
+ pr_err("%s missing clock-frequency\n", node->name);
+ goto cleanup;
+ }
+ clk_hw->fixed_rate = val;
+
+ if (of_property_read_u32(node, "ti,bit-shift", &val)) {
+ pr_err("%s missing bit-shift\n", node->name);
+ goto cleanup;
+ }
+
+ clk_hw->enable_bit = val;
+ ad->enable_mask = 0x3 << val;
+ ad->autoidle_mask = 0x3 << val;
+
+ if (of_property_read_u32(node, "ti,idlest-shift", &val)) {
+ pr_err("%s missing idlest-shift\n", node->name);
+ goto cleanup;
+ }
+
+ ad->idlest_mask = 1 << val;
+
+ ad->control_reg = ti_clk_get_reg_addr(node, 0);
+ ad->autoidle_reg = ti_clk_get_reg_addr(node, 1);
+ ad->idlest_reg = ti_clk_get_reg_addr(node, 2);
+
+ if (!ad->control_reg || !ad->autoidle_reg || !ad->idlest_reg)
+ goto cleanup;
+
+ clk = clk_register(NULL, &clk_hw->hw);
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ kfree(init);
+ return;
+ }
+cleanup:
+ kfree(ad);
+ kfree(clk_hw);
+ kfree(init);
+}
+CLK_OF_DECLARE(omap2_apll_clock, "ti,omap2-apll-clock",
+ of_omap2_apll_setup);