[PATCH] clk: ingenic: Allow divider value to be right shifted
From: Harvey Hunt
Date: Thu Dec 24 2015 - 05:46:05 EST
The JZ4780's MSC clock divider registers multiply the clock divider
by 2. This means that MSC devices run at half their expected speed.
Shift the clock divider for the affected registers to solve this.
Signed-off-by: Harvey Hunt <harvey.hunt@xxxxxxxxxx>
---
drivers/clk/ingenic/cgu.c | 11 ++++++++++-
drivers/clk/ingenic/cgu.h | 6 +++++-
drivers/clk/ingenic/jz4740-cgu.c | 24 ++++++++++++------------
drivers/clk/ingenic/jz4780-cgu.c | 38 +++++++++++++++++++-------------------
4 files changed, 46 insertions(+), 33 deletions(-)
diff --git a/drivers/clk/ingenic/cgu.c b/drivers/clk/ingenic/cgu.c
index 7cfb7b2..8333bd0 100644
--- a/drivers/clk/ingenic/cgu.c
+++ b/drivers/clk/ingenic/cgu.c
@@ -325,6 +325,7 @@ ingenic_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
div = (div_reg >> clk_info->div.shift) &
GENMASK(clk_info->div.bits - 1, 0);
div += 1;
+ div <<= clk_info->div.div;
rate /= div;
}
@@ -345,6 +346,14 @@ ingenic_clk_calc_div(const struct ingenic_cgu_clk_info *clk_info,
div = min_t(unsigned, div, 1 << clk_info->div.bits);
div = max_t(unsigned, div, 1);
+ /*
+ * If the divider value itself must be divided before being written to
+ * the divider register, we must ensure we don't have any bits set that
+ * would be lost as a result of doing so.
+ */
+ div >>= clk_info->div.div;
+ div <<= clk_info->div.div;
+
return div;
}
@@ -395,7 +404,7 @@ ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
/* update the divide */
mask = GENMASK(clk_info->div.bits - 1, 0);
reg &= ~(mask << clk_info->div.shift);
- reg |= (div - 1) << clk_info->div.shift;
+ reg |= ((div >> clk_info->div.div) - 1) << clk_info->div.shift;
/* clear the stop bit */
if (clk_info->div.stop_bit != -1)
diff --git a/drivers/clk/ingenic/cgu.h b/drivers/clk/ingenic/cgu.h
index 99347e2..bdeac6c 100644
--- a/drivers/clk/ingenic/cgu.h
+++ b/drivers/clk/ingenic/cgu.h
@@ -76,8 +76,11 @@ struct ingenic_cgu_mux_info {
/**
* struct ingenic_cgu_div_info - information about a divider
* @reg: offset of the divider control register within the CGU
- * @shift: number of bits to shift the divide value by (ie. the index of
+ * @shift: number of bits to left shift the divide value by (ie. the index of
* the lowest bit of the divide value within its control register)
+ * @div: number of bits to right shift the divide value by (i.e. if the
+ * effective divider value is the value written to the register
+ * multiplied by some constant)
* @bits: the size of the divide value in bits
* @ce_bit: the index of the change enable bit within reg, or -1 if there
* isn't one
@@ -87,6 +90,7 @@ struct ingenic_cgu_mux_info {
struct ingenic_cgu_div_info {
unsigned reg;
u8 shift;
+ u8 div;
u8 bits;
s8 ce_bit;
s8 busy_bit;
diff --git a/drivers/clk/ingenic/jz4740-cgu.c b/drivers/clk/ingenic/jz4740-cgu.c
index 305a26c2..8d0ebad 100644
--- a/drivers/clk/ingenic/jz4740-cgu.c
+++ b/drivers/clk/ingenic/jz4740-cgu.c
@@ -90,51 +90,51 @@ static const struct ingenic_cgu_clk_info jz4740_cgu_clocks[] = {
[JZ4740_CLK_PLL_HALF] = {
"pll half", CGU_CLK_DIV,
.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
- .div = { CGU_REG_CPCCR, 21, 1, -1, -1, -1 },
+ .div = { CGU_REG_CPCCR, 21, 0, 1, -1, -1, -1 },
},
[JZ4740_CLK_CCLK] = {
"cclk", CGU_CLK_DIV,
.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
- .div = { CGU_REG_CPCCR, 0, 4, 22, -1, -1 },
+ .div = { CGU_REG_CPCCR, 0, 0, 4, 22, -1, -1 },
},
[JZ4740_CLK_HCLK] = {
"hclk", CGU_CLK_DIV,
.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
- .div = { CGU_REG_CPCCR, 4, 4, 22, -1, -1 },
+ .div = { CGU_REG_CPCCR, 4, 0, 4, 22, -1, -1 },
},
[JZ4740_CLK_PCLK] = {
"pclk", CGU_CLK_DIV,
.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
- .div = { CGU_REG_CPCCR, 8, 4, 22, -1, -1 },
+ .div = { CGU_REG_CPCCR, 8, 0, 4, 22, -1, -1 },
},
[JZ4740_CLK_MCLK] = {
"mclk", CGU_CLK_DIV,
.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
- .div = { CGU_REG_CPCCR, 12, 4, 22, -1, -1 },
+ .div = { CGU_REG_CPCCR, 12, 0, 4, 22, -1, -1 },
},
[JZ4740_CLK_LCD] = {
"lcd", CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
- .div = { CGU_REG_CPCCR, 16, 5, 22, -1, -1 },
+ .div = { CGU_REG_CPCCR, 16, 0, 5, 22, -1, -1 },
.gate = { CGU_REG_CLKGR, 10 },
},
[JZ4740_CLK_LCD_PCLK] = {
"lcd_pclk", CGU_CLK_DIV,
.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
- .div = { CGU_REG_LPCDR, 0, 11, -1, -1, -1 },
+ .div = { CGU_REG_LPCDR, 0, 0, 11, -1, -1, -1 },
},
[JZ4740_CLK_I2S] = {
"i2s", CGU_CLK_MUX | CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4740_CLK_EXT, JZ4740_CLK_PLL_HALF, -1, -1 },
.mux = { CGU_REG_CPCCR, 31, 1 },
- .div = { CGU_REG_I2SCDR, 0, 8, -1, -1, -1 },
+ .div = { CGU_REG_I2SCDR, 0, 0, 8, -1, -1, -1 },
.gate = { CGU_REG_CLKGR, 6 },
},
@@ -142,21 +142,21 @@ static const struct ingenic_cgu_clk_info jz4740_cgu_clocks[] = {
"spi", CGU_CLK_MUX | CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4740_CLK_EXT, JZ4740_CLK_PLL, -1, -1 },
.mux = { CGU_REG_SSICDR, 31, 1 },
- .div = { CGU_REG_SSICDR, 0, 4, -1, -1, -1 },
+ .div = { CGU_REG_SSICDR, 0, 0, 4, -1, -1, -1 },
.gate = { CGU_REG_CLKGR, 4 },
},
[JZ4740_CLK_MMC] = {
"mmc", CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
- .div = { CGU_REG_MSCCDR, 0, 5, -1, -1, -1 },
+ .div = { CGU_REG_MSCCDR, 0, 0, 5, -1, -1, -1 },
.gate = { CGU_REG_CLKGR, 7 },
},
[JZ4740_CLK_UHC] = {
"uhc", CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
- .div = { CGU_REG_UHCCDR, 0, 4, -1, -1, -1 },
+ .div = { CGU_REG_UHCCDR, 0, 0, 4, -1, -1, -1 },
.gate = { CGU_REG_CLKGR, 14 },
},
@@ -164,7 +164,7 @@ static const struct ingenic_cgu_clk_info jz4740_cgu_clocks[] = {
"udc", CGU_CLK_MUX | CGU_CLK_DIV,
.parents = { JZ4740_CLK_EXT, JZ4740_CLK_PLL_HALF, -1, -1 },
.mux = { CGU_REG_CPCCR, 29, 1 },
- .div = { CGU_REG_CPCCR, 23, 6, -1, -1, -1 },
+ .div = { CGU_REG_CPCCR, 23, 0, 6, -1, -1, -1 },
.gate = { CGU_REG_SCR, 6 },
},
diff --git a/drivers/clk/ingenic/jz4780-cgu.c b/drivers/clk/ingenic/jz4780-cgu.c
index 431f962..da9ac32 100644
--- a/drivers/clk/ingenic/jz4780-cgu.c
+++ b/drivers/clk/ingenic/jz4780-cgu.c
@@ -296,13 +296,13 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
[JZ4780_CLK_CPU] = {
"cpu", CGU_CLK_DIV,
.parents = { JZ4780_CLK_CPUMUX, -1, -1, -1 },
- .div = { CGU_REG_CLOCKCONTROL, 0, 4, 22, -1, -1 },
+ .div = { CGU_REG_CLOCKCONTROL, 0, 0, 4, 22, -1, -1 },
},
[JZ4780_CLK_L2CACHE] = {
"l2cache", CGU_CLK_DIV,
.parents = { JZ4780_CLK_CPUMUX, -1, -1, -1 },
- .div = { CGU_REG_CLOCKCONTROL, 4, 4, -1, -1, -1 },
+ .div = { CGU_REG_CLOCKCONTROL, 4, 0, 4, -1, -1, -1 },
},
[JZ4780_CLK_AHB0] = {
@@ -310,7 +310,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { -1, JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_EPLL },
.mux = { CGU_REG_CLOCKCONTROL, 26, 2 },
- .div = { CGU_REG_CLOCKCONTROL, 8, 4, 21, -1, -1 },
+ .div = { CGU_REG_CLOCKCONTROL, 8, 0, 4, 21, -1, -1 },
},
[JZ4780_CLK_AHB2PMUX] = {
@@ -323,20 +323,20 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
[JZ4780_CLK_AHB2] = {
"ahb2", CGU_CLK_DIV,
.parents = { JZ4780_CLK_AHB2PMUX, -1, -1, -1 },
- .div = { CGU_REG_CLOCKCONTROL, 12, 4, 20, -1, -1 },
+ .div = { CGU_REG_CLOCKCONTROL, 12, 0, 4, 20, -1, -1 },
},
[JZ4780_CLK_PCLK] = {
"pclk", CGU_CLK_DIV,
.parents = { JZ4780_CLK_AHB2PMUX, -1, -1, -1 },
- .div = { CGU_REG_CLOCKCONTROL, 16, 4, 20, -1, -1 },
+ .div = { CGU_REG_CLOCKCONTROL, 16, 0, 4, 20, -1, -1 },
},
[JZ4780_CLK_DDR] = {
"ddr", CGU_CLK_MUX | CGU_CLK_DIV,
.parents = { -1, JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL, -1 },
.mux = { CGU_REG_DDRCDR, 30, 2 },
- .div = { CGU_REG_DDRCDR, 0, 4, 29, 28, 27 },
+ .div = { CGU_REG_DDRCDR, 0, 0, 4, 29, 28, 27 },
},
[JZ4780_CLK_VPU] = {
@@ -344,7 +344,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_EPLL, -1 },
.mux = { CGU_REG_VPUCDR, 30, 2 },
- .div = { CGU_REG_VPUCDR, 0, 4, 29, 28, 27 },
+ .div = { CGU_REG_VPUCDR, 0, 0, 4, 29, 28, 27 },
.gate = { CGU_REG_CLKGR1, 2 },
},
@@ -352,7 +352,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
"i2s_pll", CGU_CLK_MUX | CGU_CLK_DIV,
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_EPLL, -1, -1 },
.mux = { CGU_REG_I2SCDR, 30, 1 },
- .div = { CGU_REG_I2SCDR, 0, 8, 29, 28, 27 },
+ .div = { CGU_REG_I2SCDR, 0, 0, 8, 29, 28, 27 },
},
[JZ4780_CLK_I2S] = {
@@ -366,7 +366,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_VPLL, -1 },
.mux = { CGU_REG_LP0CDR, 30, 2 },
- .div = { CGU_REG_LP0CDR, 0, 8, 28, 27, 26 },
+ .div = { CGU_REG_LP0CDR, 0, 0, 8, 28, 27, 26 },
},
[JZ4780_CLK_LCD1PIXCLK] = {
@@ -374,7 +374,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_VPLL, -1 },
.mux = { CGU_REG_LP1CDR, 30, 2 },
- .div = { CGU_REG_LP1CDR, 0, 8, 28, 27, 26 },
+ .div = { CGU_REG_LP1CDR, 0, 0, 8, 28, 27, 26 },
},
[JZ4780_CLK_MSCMUX] = {
@@ -386,21 +386,21 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
[JZ4780_CLK_MSC0] = {
"msc0", CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4780_CLK_MSCMUX, -1, -1, -1 },
- .div = { CGU_REG_MSC0CDR, 0, 8, 29, 28, 27 },
+ .div = { CGU_REG_MSC0CDR, 0, 1, 8, 29, 28, 27 },
.gate = { CGU_REG_CLKGR0, 3 },
},
[JZ4780_CLK_MSC1] = {
"msc1", CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4780_CLK_MSCMUX, -1, -1, -1 },
- .div = { CGU_REG_MSC1CDR, 0, 8, 29, 28, 27 },
+ .div = { CGU_REG_MSC1CDR, 0, 1, 8, 29, 28, 27 },
.gate = { CGU_REG_CLKGR0, 11 },
},
[JZ4780_CLK_MSC2] = {
"msc2", CGU_CLK_DIV | CGU_CLK_GATE,
.parents = { JZ4780_CLK_MSCMUX, -1, -1, -1 },
- .div = { CGU_REG_MSC2CDR, 0, 8, 29, 28, 27 },
+ .div = { CGU_REG_MSC2CDR, 0, 1, 8, 29, 28, 27 },
.gate = { CGU_REG_CLKGR0, 12 },
},
@@ -409,7 +409,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_EPLL, JZ4780_CLK_OTGPHY },
.mux = { CGU_REG_UHCCDR, 30, 2 },
- .div = { CGU_REG_UHCCDR, 0, 8, 29, 28, 27 },
+ .div = { CGU_REG_UHCCDR, 0, 0, 8, 29, 28, 27 },
.gate = { CGU_REG_CLKGR0, 24 },
},
@@ -417,7 +417,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
"ssi_pll", CGU_CLK_MUX | CGU_CLK_DIV,
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL, -1, -1 },
.mux = { CGU_REG_SSICDR, 30, 1 },
- .div = { CGU_REG_SSICDR, 0, 8, 29, 28, 27 },
+ .div = { CGU_REG_SSICDR, 0, 0, 8, 29, 28, 27 },
},
[JZ4780_CLK_SSI] = {
@@ -430,7 +430,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
"cim_mclk", CGU_CLK_MUX | CGU_CLK_DIV,
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL, -1, -1 },
.mux = { CGU_REG_CIMCDR, 31, 1 },
- .div = { CGU_REG_CIMCDR, 0, 8, 30, 29, 28 },
+ .div = { CGU_REG_CIMCDR, 0, 0, 8, 30, 29, 28 },
},
[JZ4780_CLK_PCMPLL] = {
@@ -438,7 +438,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_EPLL, JZ4780_CLK_VPLL },
.mux = { CGU_REG_PCMCDR, 29, 2 },
- .div = { CGU_REG_PCMCDR, 0, 8, 28, 27, 26 },
+ .div = { CGU_REG_PCMCDR, 0, 0, 8, 28, 27, 26 },
},
[JZ4780_CLK_PCM] = {
@@ -453,7 +453,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { -1, JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_EPLL },
.mux = { CGU_REG_GPUCDR, 30, 2 },
- .div = { CGU_REG_GPUCDR, 0, 4, 29, 28, 27 },
+ .div = { CGU_REG_GPUCDR, 0, 0, 4, 29, 28, 27 },
.gate = { CGU_REG_CLKGR1, 4 },
},
@@ -471,7 +471,7 @@ static const struct ingenic_cgu_clk_info jz4780_cgu_clocks[] = {
.parents = { -1, JZ4780_CLK_SCLKA, JZ4780_CLK_MPLL,
JZ4780_CLK_EPLL },
.mux = { CGU_REG_BCHCDR, 30, 2 },
- .div = { CGU_REG_BCHCDR, 0, 4, 29, 28, 27 },
+ .div = { CGU_REG_BCHCDR, 0, 0, 4, 29, 28, 27 },
.gate = { CGU_REG_CLKGR0, 1 },
},
--
2.6.4
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