From: Kevin Cernekee <[email protected]> When setting the PLL rates, check that:
- VCO is within range - PFD is within range - PLL is disabled when postdiv is changed - postdiv2 <= postdiv1 Signed-off-by: Kevin Cernekee <[email protected]> Signed-off-by: Ezequiel Garcia <[email protected]> --- drivers/clk/pistachio/clk-pll.c | 83 +++++++++++++++++++++++++++++++++++++++-- 1 file changed, 79 insertions(+), 4 deletions(-) diff --git a/drivers/clk/pistachio/clk-pll.c b/drivers/clk/pistachio/clk-pll.c index cf000bb..59728bb 100644 --- a/drivers/clk/pistachio/clk-pll.c +++ b/drivers/clk/pistachio/clk-pll.c @@ -6,9 +6,12 @@ * version 2, as published by the Free Software Foundation. */ +#define pr_fmt(fmt) "%s: " fmt, __func__ + #include <linux/clk-provider.h> #include <linux/io.h> #include <linux/kernel.h> +#include <linux/printk.h> #include <linux/slab.h> #include "clk.h" @@ -50,6 +53,18 @@ #define PLL_CTRL4 0x10 #define PLL_FRAC_CTRL4_BYPASS BIT(28) +#define MIN_PFD 9600000UL +#define MIN_VCO_LA 400000000UL +#define MAX_VCO_LA 1600000000UL +#define MIN_VCO_FRAC_INT 600000000UL +#define MAX_VCO_FRAC_INT 1600000000UL +#define MIN_VCO_FRAC_FRAC 600000000UL +#define MAX_VCO_FRAC_FRAC 2400000000UL +#define MIN_OUTPUT_LA 8000000UL +#define MAX_OUTPUT_LA 1600000000UL +#define MIN_OUTPUT_FRAC 12000000UL +#define MAX_OUTPUT_FRAC 1600000000UL + struct pistachio_clk_pll { struct clk_hw hw; void __iomem *base; @@ -179,12 +194,29 @@ static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate, struct pistachio_clk_pll *pll = to_pistachio_pll(hw); struct pistachio_pll_rate_table *params; int enabled = pll_gf40lp_frac_is_enabled(hw); - u32 val, frac; + u32 val, frac, vco, old_postdiv1, old_postdiv2; + const char *name = __clk_get_name(hw->clk); + + if (rate < MIN_OUTPUT_FRAC || rate > MAX_OUTPUT_FRAC) + return -EINVAL; params = pll_get_params(pll, parent_rate, rate); - if (!params) + if (!params || !params->refdiv) return -EINVAL; + vco = params->fref * params->fbdiv / params->refdiv; + if (vco < MIN_VCO_FRAC_FRAC || vco > MAX_VCO_FRAC_FRAC) + pr_warn("%s: VCO %u is out of range %lu..%lu\n", name, vco, + MIN_VCO_FRAC_FRAC, MAX_VCO_FRAC_FRAC); + + val = params->fref / params->refdiv; + if (val < MIN_PFD) + pr_warn("%s: PFD %u is too low (min %lu)\n", + name, val, MIN_PFD); + if (val > vco / 16) + pr_warn("%s: PFD %u is too high (max %u)\n", + name, val, vco / 16); + /* Calculate the frac parameter */ frac = rate * params->refdiv * params->postdiv1 * params->postdiv2; frac -= (params->fbdiv * parent_rate); @@ -198,6 +230,19 @@ static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate, pll_writel(pll, val, PLL_CTRL1); val = pll_readl(pll, PLL_CTRL2); + + old_postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) & + PLL_FRAC_CTRL2_POSTDIV1_MASK; + old_postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) & + PLL_FRAC_CTRL2_POSTDIV2_MASK; + if (enabled && + (params->postdiv1 != old_postdiv1 || + params->postdiv2 != old_postdiv2)) + pr_warn("%s: changing postdiv while PLL is enabled\n", name); + + if (params->postdiv2 > params->postdiv1) + pr_warn("%s: postdiv2 should not exceed postdiv1\n", name); + val &= ~((PLL_FRAC_CTRL2_FRAC_MASK << PLL_FRAC_CTRL2_FRAC_SHIFT) | (PLL_FRAC_CTRL2_POSTDIV1_MASK << PLL_FRAC_CTRL2_POSTDIV1_SHIFT) | @@ -296,13 +341,43 @@ static int pll_gf40lp_laint_set_rate(struct clk_hw *hw, unsigned long rate, struct pistachio_clk_pll *pll = to_pistachio_pll(hw); struct pistachio_pll_rate_table *params; int enabled = pll_gf40lp_laint_is_enabled(hw); - u32 val; + u32 val, vco, old_postdiv1, old_postdiv2; + const char *name = __clk_get_name(hw->clk); + + if (rate < MIN_OUTPUT_LA || rate > MAX_OUTPUT_LA) + return -EINVAL; params = pll_get_params(pll, parent_rate, rate); - if (!params) + if (!params || !params->refdiv) return -EINVAL; + vco = params->fref * params->fbdiv / params->refdiv; + if (vco < MIN_VCO_LA || vco > MAX_VCO_LA) + pr_warn("%s: VCO %u is out of range %lu..%lu\n", name, vco, + MIN_VCO_LA, MAX_VCO_LA); + + val = params->fref / params->refdiv; + if (val < MIN_PFD) + pr_warn("%s: PFD %u is too low (min %lu)\n", + name, val, MIN_PFD); + if (val > vco / 16) + pr_warn("%s: PFD %u is too high (max %u)\n", + name, val, vco / 16); + val = pll_readl(pll, PLL_CTRL1); + + old_postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) & + PLL_INT_CTRL1_POSTDIV1_MASK; + old_postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) & + PLL_INT_CTRL1_POSTDIV2_MASK; + if (enabled && + (params->postdiv1 != old_postdiv1 || + params->postdiv2 != old_postdiv2)) + pr_warn("%s: changing postdiv while PLL is enabled\n", name); + + if (params->postdiv2 > params->postdiv1) + pr_warn("%s: postdiv2 should not exceed postdiv1\n", name); + val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) | (PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT) | (PLL_INT_CTRL1_POSTDIV1_MASK << PLL_INT_CTRL1_POSTDIV1_SHIFT) | -- 2.3.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
