From 4d008589e271e28eae728eef7f5fb1f658f12b9f Mon Sep 17 00:00:00 2001 From: Tero Kristo Date: Mon, 24 Feb 2014 16:06:34 +0200 Subject: 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 --- .../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@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 f6e9904..eb441d1 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); -}; - unsigned long omap_fixed_divisor_recalc(struct clk_hw *hw, unsigned long parent_rate); 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 753878c..44bf840 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 -- cgit v1.1