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 --- drivers/clk/ti/apll.c | 181 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 181 insertions(+) (limited to 'drivers/clk/ti') 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); -- cgit v1.2.3