From 3526f74fa925e44335b94ed0c9f93648e26058ef Mon Sep 17 00:00:00 2001 From: Kelvin Cheung Date: Fri, 10 Oct 2014 11:42:51 +0800 Subject: [PATCH] clk: ls1x: Update relationship among all clocks - Add clock lookups for APB devices. - Update clock relationship to make it more exact and clear. _____ _______________________| | OSC ___/ | MUX |___ XXX CLK \___ PLL ___ XXX DIV ___| | |_____| Signed-off-by: Kelvin Cheung Cc: linux-kernel@vger.kernel.org Cc: mturquette@linaro.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8026/ Signed-off-by: Ralf Baechle --- drivers/clk/clk-ls1x.c | 103 ++++++++++++++++++++++++++++++----------- 1 file changed, 77 insertions(+), 26 deletions(-) diff --git a/drivers/clk/clk-ls1x.c b/drivers/clk/clk-ls1x.c index f20b750235f6..ca80103ac188 100644 --- a/drivers/clk/clk-ls1x.c +++ b/drivers/clk/clk-ls1x.c @@ -15,7 +15,8 @@ #include -#define OSC 33 +#define OSC (33 * 1000000) +#define DIV_APB 2 static DEFINE_SPINLOCK(_lock); @@ -29,13 +30,12 @@ static void ls1x_pll_clk_disable(struct clk_hw *hw) } static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw, - unsigned long parent_rate) + unsigned long parent_rate) { u32 pll, rate; pll = __raw_readl(LS1X_CLK_PLL_FREQ); - rate = ((12 + (pll & 0x3f)) * 1000000) + - ((((pll >> 8) & 0x3ff) * 1000000) >> 10); + rate = 12 + (pll & 0x3f) + (((pll >> 8) & 0x3ff) >> 10); rate *= OSC; rate >>= 1; @@ -48,8 +48,10 @@ static const struct clk_ops ls1x_pll_clk_ops = { .recalc_rate = ls1x_pll_recalc_rate, }; -static struct clk * __init clk_register_pll(struct device *dev, - const char *name, const char *parent_name, unsigned long flags) +static struct clk *__init clk_register_pll(struct device *dev, + const char *name, + const char *parent_name, + unsigned long flags) { struct clk_hw *hw; struct clk *clk; @@ -78,34 +80,83 @@ static struct clk * __init clk_register_pll(struct device *dev, return clk; } +static const char const *cpu_parents[] = { "cpu_clk_div", "osc_33m_clk", }; +static const char const *ahb_parents[] = { "ahb_clk_div", "osc_33m_clk", }; +static const char const *dc_parents[] = { "dc_clk_div", "osc_33m_clk", }; + void __init ls1x_clk_init(void) { struct clk *clk; - clk = clk_register_pll(NULL, "pll_clk", NULL, CLK_IS_ROOT); - clk_prepare_enable(clk); + clk = clk_register_fixed_rate(NULL, "osc_33m_clk", NULL, CLK_IS_ROOT, + OSC); + clk_register_clkdev(clk, "osc_33m_clk", NULL); - clk = clk_register_divider(NULL, "cpu_clk", "pll_clk", - CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_CPU_SHIFT, - DIV_CPU_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock); - clk_prepare_enable(clk); - clk_register_clkdev(clk, "cpu", NULL); + /* clock derived from 33 MHz OSC clk */ + clk = clk_register_pll(NULL, "pll_clk", "osc_33m_clk", 0); + clk_register_clkdev(clk, "pll_clk", NULL); - clk = clk_register_divider(NULL, "dc_clk", "pll_clk", - CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT, - DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock); - clk_prepare_enable(clk); - clk_register_clkdev(clk, "dc", NULL); + /* clock derived from PLL clk */ + /* _____ + * _______________________| | + * OSC ___/ | MUX |___ CPU CLK + * \___ PLL ___ CPU DIV ___| | + * |_____| + */ + clk = clk_register_divider(NULL, "cpu_clk_div", "pll_clk", + CLK_GET_RATE_NOCACHE, LS1X_CLK_PLL_DIV, + DIV_CPU_SHIFT, DIV_CPU_WIDTH, + CLK_DIVIDER_ONE_BASED | + CLK_DIVIDER_ROUND_CLOSEST, &_lock); + clk_register_clkdev(clk, "cpu_clk_div", NULL); + clk = clk_register_mux(NULL, "cpu_clk", cpu_parents, + ARRAY_SIZE(cpu_parents), + CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV, + BYPASS_CPU_SHIFT, BYPASS_CPU_WIDTH, 0, &_lock); + clk_register_clkdev(clk, "cpu_clk", NULL); - clk = clk_register_divider(NULL, "ahb_clk", "pll_clk", - CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT, - DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock); - clk_prepare_enable(clk); - clk_register_clkdev(clk, "ahb", NULL); + /* _____ + * _______________________| | + * OSC ___/ | MUX |___ DC CLK + * \___ PLL ___ DC DIV ___| | + * |_____| + */ + clk = clk_register_divider(NULL, "dc_clk_div", "pll_clk", + 0, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT, + DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock); + clk_register_clkdev(clk, "dc_clk_div", NULL); + clk = clk_register_mux(NULL, "dc_clk", dc_parents, + ARRAY_SIZE(dc_parents), + CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV, + BYPASS_DC_SHIFT, BYPASS_DC_WIDTH, 0, &_lock); + clk_register_clkdev(clk, "dc_clk", NULL); + + /* _____ + * _______________________| | + * OSC ___/ | MUX |___ DDR CLK + * \___ PLL ___ DDR DIV ___| | + * |_____| + */ + clk = clk_register_divider(NULL, "ahb_clk_div", "pll_clk", + 0, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT, + DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED, + &_lock); + clk_register_clkdev(clk, "ahb_clk_div", NULL); + clk = clk_register_mux(NULL, "ahb_clk", ahb_parents, + ARRAY_SIZE(ahb_parents), + CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV, + BYPASS_DDR_SHIFT, BYPASS_DDR_WIDTH, 0, &_lock); + clk_register_clkdev(clk, "ahb_clk", NULL); clk_register_clkdev(clk, "stmmaceth", NULL); - clk = clk_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1, 2); - clk_prepare_enable(clk); - clk_register_clkdev(clk, "apb", NULL); + /* clock derived from AHB clk */ + /* APB clk is always half of the AHB clk */ + clk = clk_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1, + DIV_APB); + clk_register_clkdev(clk, "apb_clk", NULL); + clk_register_clkdev(clk, "ls1x_i2c", NULL); + clk_register_clkdev(clk, "ls1x_pwmtimer", NULL); + clk_register_clkdev(clk, "ls1x_spi", NULL); + clk_register_clkdev(clk, "ls1x_wdt", NULL); clk_register_clkdev(clk, "serial8250", NULL); }