[PATCHv2 05/14] CLK: TI: APLL: add support for omap2 aplls
Tero Kristo
t-kristo at ti.com
Tue Mar 4 04:18:11 EST 2014
This patch adds support for omap2 type aplls, which have gating and
autoidle functionality.
Signed-off-by: Tero Kristo <t-kristo at ti.com>
---
.../devicetree/bindings/clock/ti/apll.txt | 24 ++-
arch/arm/mach-omap2/clock.h | 11 --
drivers/clk/ti/apll.c | 181 ++++++++++++++++++++
include/linux/clk/ti.h | 21 ++-
4 files changed, 220 insertions(+), 17 deletions(-)
diff --git a/Documentation/devicetree/bindings/clock/ti/apll.txt b/Documentation/devicetree/bindings/clock/ti/apll.txt
index 7faf5a6..ade4dd4 100644
--- a/Documentation/devicetree/bindings/clock/ti/apll.txt
+++ b/Documentation/devicetree/bindings/clock/ti/apll.txt
@@ -14,18 +14,32 @@ a subtype of a DPLL [2], although a simplified one at that.
[2] Documentation/devicetree/bindings/clock/ti/dpll.txt
Required properties:
-- compatible : shall be "ti,dra7-apll-clock"
+- compatible : shall be "ti,dra7-apll-clock" or "ti,omap2-apll-clock"
- #clock-cells : from common clock binding; shall be set to 0.
- clocks : link phandles of parent clocks (clk-ref and clk-bypass)
- reg : address and length of the register set for controlling the APLL.
It contains the information of registers in the following order:
- "control" - contains the control register base address
- "idlest" - contains the idlest register base address
+ "control" - contains the control register offset
+ "idlest" - contains the idlest register offset
+ "autoidle" - contains the autoidle register offset (OMAP2 only)
+- ti,clock-frequency : static clock frequency for the clock (OMAP2 only)
+- ti,idlest-shift : bit-shift for the idlest field (OMAP2 only)
+- ti,bit-shift : bit-shift for enable and autoidle fields (OMAP2 only)
Examples:
- apll_pcie_ck: apll_pcie_ck at 4a008200 {
+ apll_pcie_ck: apll_pcie_ck {
#clock-cells = <0>;
clocks = <&apll_pcie_in_clk_mux>, <&dpll_pcie_ref_ck>;
- reg = <0x4a00821c 0x4>, <0x4a008220 0x4>;
+ reg = <0x021c>, <0x0220>;
compatible = "ti,dra7-apll-clock";
};
+
+ apll96_ck: apll96_ck {
+ #clock-cells = <0>;
+ compatible = "ti,omap2-apll-clock";
+ clocks = <&sys_ck>;
+ ti,bit-shift = <2>;
+ ti,idlest-shift = <8>;
+ ti,clock-frequency = <96000000>;
+ reg = <0x0500>, <0x0530>, <0x0520>;
+ };
diff --git a/arch/arm/mach-omap2/clock.h b/arch/arm/mach-omap2/clock.h
index 7057f37..7b7a03c 100644
--- a/arch/arm/mach-omap2/clock.h
+++ b/arch/arm/mach-omap2/clock.h
@@ -178,17 +178,6 @@ struct clksel {
const struct clksel_rate *rates;
};
-struct clk_hw_omap_ops {
- void (*find_idlest)(struct clk_hw_omap *oclk,
- void __iomem **idlest_reg,
- u8 *idlest_bit, u8 *idlest_val);
- void (*find_companion)(struct clk_hw_omap *oclk,
- void __iomem **other_reg,
- u8 *other_bit);
- void (*allow_idle)(struct clk_hw_omap *oclk);
- void (*deny_idle)(struct clk_hw_omap *oclk);
-};
-
/* CM_CLKSEL2_PLL.CORE_CLK_SRC bits (2XXX) */
#define CORE_CLK_SRC_32K 0x0
#define CORE_CLK_SRC_DPLL 0x1
diff --git a/drivers/clk/ti/apll.c b/drivers/clk/ti/apll.c
index b986f61..5428c9c 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);
diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h
index 2310adc..ddac0d0 100644
--- a/include/linux/clk/ti.h
+++ b/include/linux/clk/ti.h
@@ -94,7 +94,26 @@ struct dpll_data {
u8 flags;
};
-struct clk_hw_omap_ops;
+struct clk_hw_omap;
+
+/**
+ * struct clk_hw_omap_ops - OMAP clk ops
+ * @find_idlest: find idlest register information for a clock
+ * @find_companion: find companion clock register information for a clock,
+ * basically converts CM_ICLKEN* <-> CM_FCLKEN*
+ * @allow_idle: enables autoidle hardware functionality for a clock
+ * @deny_idle: prevent autoidle hardware functionality for a clock
+ */
+struct clk_hw_omap_ops {
+ void (*find_idlest)(struct clk_hw_omap *oclk,
+ void __iomem **idlest_reg,
+ u8 *idlest_bit, u8 *idlest_val);
+ void (*find_companion)(struct clk_hw_omap *oclk,
+ void __iomem **other_reg,
+ u8 *other_bit);
+ void (*allow_idle)(struct clk_hw_omap *oclk);
+ void (*deny_idle)(struct clk_hw_omap *oclk);
+};
/**
* struct clk_hw_omap - OMAP struct clk
--
1.7.9.5
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