[PATCH] ARM: imx: pllv3: add shift for frequency multiplier

From: Stefan Agner
Date: Tue Dec 02 2014 - 12:00:00 EST


Add shift capabilties for the frequency multiplier (DIV_SELECT) to
support Vybrid's USB PLL oddity. The PLL3 and PLL7 are the only
PLL control registers which have the DIV_SELECT bit shifted by
one. Be aware, there are known documentation errors in the
reference manual too.

Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
I first thought of an additional parameter for clk_pllv3_recalc_rate,
but since this function is used in multiple SoCs it would have made
the change much larger. By creating a new type for Vybrid's USB PLL
it is also much more explicit that the USB PLL's on Vybrid are
different to the others...

arch/arm/mach-imx/clk-pllv3.c | 10 +++++++---
arch/arm/mach-imx/clk-vf610.c | 4 ++--
arch/arm/mach-imx/clk.h | 1 +
3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-imx/clk-pllv3.c b/arch/arm/mach-imx/clk-pllv3.c
index 0ad6e54..641ebc5 100644
--- a/arch/arm/mach-imx/clk-pllv3.c
+++ b/arch/arm/mach-imx/clk-pllv3.c
@@ -31,6 +31,7 @@
* @base: base address of PLL registers
* @powerup_set: set POWER bit to power up the PLL
* @div_mask: mask of divider bits
+ * @div_shift: shift of divider bits
*
* IMX PLL clock version 3, found on i.MX6 series. Divider for pllv3
* is actually a multiplier, and always sits at bit 0.
@@ -40,6 +41,7 @@ struct clk_pllv3 {
void __iomem *base;
bool powerup_set;
u32 div_mask;
+ u32 div_shift;
};

#define to_clk_pllv3(_hw) container_of(_hw, struct clk_pllv3, hw)
@@ -97,7 +99,7 @@ static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_pllv3 *pll = to_clk_pllv3(hw);
- u32 div = readl_relaxed(pll->base) & pll->div_mask;
+ u32 div = (readl_relaxed(pll->base) >> pll->div_shift) & pll->div_mask;

return (div == 1) ? parent_rate * 22 : parent_rate * 20;
}
@@ -125,8 +127,8 @@ static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate,
return -EINVAL;

val = readl_relaxed(pll->base);
- val &= ~pll->div_mask;
- val |= div;
+ val &= ~(pll->div_mask << pll->div_shift);
+ val |= (div << pll->div_shift);
writel_relaxed(val, pll->base);

return clk_pllv3_wait_lock(pll);
@@ -295,6 +297,8 @@ struct clk *imx_clk_pllv3(enum imx_pllv3_type type, const char *name,
case IMX_PLLV3_SYS:
ops = &clk_pllv3_sys_ops;
break;
+ case IMX_PLLV3_USB_VF610:
+ pll->div_shift = 1;
case IMX_PLLV3_USB:
ops = &clk_pllv3_ops;
pll->powerup_set = true;
diff --git a/arch/arm/mach-imx/clk-vf610.c b/arch/arm/mach-imx/clk-vf610.c
index 5937dde..cb21777 100644
--- a/arch/arm/mach-imx/clk-vf610.c
+++ b/arch/arm/mach-imx/clk-vf610.c
@@ -172,11 +172,11 @@ static void __init vf610_clocks_init(struct device_node *ccm_node)

clk[VF610_CLK_PLL1] = imx_clk_pllv3(IMX_PLLV3_GENERIC, "pll1", "pll1_bypass_src", PLL1_CTRL, 0x1);
clk[VF610_CLK_PLL2] = imx_clk_pllv3(IMX_PLLV3_GENERIC, "pll2", "pll2_bypass_src", PLL2_CTRL, 0x1);
- clk[VF610_CLK_PLL3] = imx_clk_pllv3(IMX_PLLV3_USB, "pll3", "pll3_bypass_src", PLL3_CTRL, 0x1);
+ clk[VF610_CLK_PLL3] = imx_clk_pllv3(IMX_PLLV3_USB_VF610, "pll3", "pll3_bypass_src", PLL3_CTRL, 0x2);
clk[VF610_CLK_PLL4] = imx_clk_pllv3(IMX_PLLV3_AV, "pll4", "pll4_bypass_src", PLL4_CTRL, 0x7f);
clk[VF610_CLK_PLL5] = imx_clk_pllv3(IMX_PLLV3_ENET, "pll5", "pll5_bypass_src", PLL5_CTRL, 0x3);
clk[VF610_CLK_PLL6] = imx_clk_pllv3(IMX_PLLV3_AV, "pll6", "pll6_bypass_src", PLL6_CTRL, 0x7f);
- clk[VF610_CLK_PLL7] = imx_clk_pllv3(IMX_PLLV3_USB, "pll7", "pll7_bypass_src", PLL7_CTRL, 0x1);
+ clk[VF610_CLK_PLL7] = imx_clk_pllv3(IMX_PLLV3_USB_VF610, "pll7", "pll7_bypass_src", PLL7_CTRL, 0x2);

clk[VF610_PLL1_BYPASS] = imx_clk_mux_flags("pll1_bypass", PLL1_CTRL, 16, 1, pll1_bypass_sels, ARRAY_SIZE(pll1_bypass_sels), CLK_SET_RATE_PARENT);
clk[VF610_PLL2_BYPASS] = imx_clk_mux_flags("pll2_bypass", PLL2_CTRL, 16, 1, pll2_bypass_sels, ARRAY_SIZE(pll2_bypass_sels), CLK_SET_RATE_PARENT);
diff --git a/arch/arm/mach-imx/clk.h b/arch/arm/mach-imx/clk.h
index 5ef82e2..6a07903 100644
--- a/arch/arm/mach-imx/clk.h
+++ b/arch/arm/mach-imx/clk.h
@@ -20,6 +20,7 @@ enum imx_pllv3_type {
IMX_PLLV3_GENERIC,
IMX_PLLV3_SYS,
IMX_PLLV3_USB,
+ IMX_PLLV3_USB_VF610,
IMX_PLLV3_AV,
IMX_PLLV3_ENET,
};
--
2.1.3

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