From: Amit Singh Tomar amittomer25@gmail.com
This commit adds SD/MMC clocks, and provides .set/get_rate callbacks for SD/MMC device present on Actions OWL S700 SoCs.
Signed-off-by: Amit Singh Tomar amittomer25@gmail.com --- Changes since v2: * Fixed the not weird div assignment. * Moved the clock bit for SD from header file to driver file. * Removed "< 0" part while comparing unsigned. Changes since previous version: * Removed rate *= 2 as this just overclocks. * Separated the divide by 128 bit from divider value. * Provided the separate routine to get sd parent rate based on bit 9. * Removed unnecessary initialization. --- drivers/clk/owl/clk_owl.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+)
diff --git a/drivers/clk/owl/clk_owl.c b/drivers/clk/owl/clk_owl.c index 5be1b3b..34cee7d 100644 --- a/drivers/clk/owl/clk_owl.c +++ b/drivers/clk/owl/clk_owl.c @@ -20,6 +20,8 @@ #include <linux/bitops.h> #include <linux/delay.h>
+#define CMU_DEVCLKEN0_SD0 BIT(22) + void owl_clk_init(struct owl_clk_priv *priv) { u32 bus_clk = 0, core_pll, dev_pll; @@ -92,6 +94,9 @@ int owl_clk_enable(struct clk *clk) setbits_le32(priv->base + CMU_DEVCLKEN1, CMU_DEVCLKEN1_ETH); setbits_le32(priv->base + CMU_ETHERNETPLL, 5); break; + case CLK_SD0: + setbits_le32(priv->base + CMU_DEVCLKEN0, CMU_DEVCLKEN0_SD0); + break; default: return -EINVAL; } @@ -121,6 +126,9 @@ int owl_clk_disable(struct clk *clk) case CLK_ETHERNET: clrbits_le32(priv->base + CMU_DEVCLKEN1, CMU_DEVCLKEN1_ETH); break; + case CLK_SD0: + clrbits_le32(priv->base + CMU_DEVCLKEN0, CMU_DEVCLKEN0_SD0); + break; default: return -EINVAL; } @@ -128,11 +136,72 @@ int owl_clk_disable(struct clk *clk) return 0; }
+static ulong get_sd_parent_rate(struct owl_clk_priv *priv, u32 dev_index) +{ + ulong rate; + u32 reg; + + reg = readl(priv->base + (CMU_SD0CLK + dev_index * 0x4)); + /* Clock output of DEV/NAND_PLL + * Range: 48M ~ 756M + * Frequency= PLLCLK * 6 + */ + if (reg & 0x200) + rate = readl(priv->base + CMU_NANDPLL) & 0x7f; + else + rate = readl(priv->base + CMU_DEVPLL) & 0x7f; + + rate *= 6000000; + + return rate; +} + +static ulong owl_get_sd_clk_rate(struct owl_clk_priv *priv, int sd_index) +{ + uint div, val; + ulong parent_rate = get_sd_parent_rate(priv, sd_index); + + val = readl(priv->base + (CMU_SD0CLK + sd_index * 0x4)); + div = (val & 0x1f) + 1; + + return (parent_rate / div); +} + +static ulong owl_set_sd_clk_rate(struct owl_clk_priv *priv, ulong rate, + int sd_index) +{ + uint div, val; + ulong parent_rate = get_sd_parent_rate(priv, sd_index); + + if (rate == 0) + return rate; + + div = (parent_rate / rate); + + val = readl(priv->base + (CMU_SD0CLK + sd_index * 0x4)); + /* Bits 4..0 is used to program div value and bit 8 to enable + * divide by 128 circuit + */ + val &= ~0x11f; + if (div >= 128) { + div = div / 128; + val |= 0x100; /* enable divide by 128 circuit */ + } + val |= ((div - 1) & 0x1f); + writel(val, priv->base + (CMU_SD0CLK + sd_index * 0x4)); + + return owl_get_sd_clk_rate(priv, 0); +} + static ulong owl_clk_get_rate(struct clk *clk) { + struct owl_clk_priv *priv = dev_get_priv(clk->dev); ulong rate;
switch (clk->id) { + case CLK_SD0: + rate = owl_get_sd_clk_rate(priv, 0); + break; default: return -ENOENT; } @@ -142,9 +211,13 @@ static ulong owl_clk_get_rate(struct clk *clk)
static ulong owl_clk_set_rate(struct clk *clk, ulong rate) { + struct owl_clk_priv *priv = dev_get_priv(clk->dev); ulong new_rate;
switch (clk->id) { + case CLK_SD0: + new_rate = owl_set_sd_clk_rate(priv, rate, 0); + break; default: return -ENOENT; }