Message ID | 1422952026-12292-8-git-send-email-akshay.s@samsung.com |
---|---|
State | Changes Requested |
Delegated to: | Minkyu Kang |
Headers | show |
Hi Akshay, On 02/03/2015 05:27 PM, Akshay Saraswat wrote: > Cleaning up soc_get_periph_rate to make the logic easy to > comprehend. > Could you give more detailed description? > Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> > --- > Changes since v4: > - New patch. > > arch/arm/cpu/armv7/exynos/clock.c | 76 +++++++++++++++++---------------------- > 1 file changed, 33 insertions(+), 43 deletions(-) > > diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c > index 3884d4b..8724bc7 100644 > --- a/arch/arm/cpu/armv7/exynos/clock.c > +++ b/arch/arm/cpu/armv7/exynos/clock.c > @@ -366,8 +366,8 @@ static struct clk_bit_info *get_clk_bit_info(int peripheral) > static unsigned long exynos5_get_periph_rate(int peripheral) > { > struct clk_bit_info *bit_info = get_clk_bit_info(peripheral); > - unsigned long sclk, sub_clk = 0; > - unsigned int src, div, sub_div = 0; > + unsigned long sclk = 0; > + unsigned int src = 0, div = 0, sub_div = 0; > struct exynos5_clock *clk = > (struct exynos5_clock *)samsung_get_base_clock(); > > @@ -389,30 +389,30 @@ static unsigned long exynos5_get_periph_rate(int peripheral) > break; > case PERIPH_ID_I2S0: > src = readl(&clk->src_mau); > - div = readl(&clk->div_mau); > + div = sub_div = readl(&clk->div_mau); > case PERIPH_ID_SPI0: > case PERIPH_ID_SPI1: > src = readl(&clk->src_peric1); > - div = readl(&clk->div_peric1); > + div = sub_div = readl(&clk->div_peric1); > break; > case PERIPH_ID_SPI2: > src = readl(&clk->src_peric1); > - div = readl(&clk->div_peric2); > + div = sub_div = readl(&clk->div_peric2); > break; > case PERIPH_ID_SPI3: > case PERIPH_ID_SPI4: > src = readl(&clk->sclk_src_isp); > - div = readl(&clk->sclk_div_isp); > + div = sub_div = readl(&clk->sclk_div_isp); > break; > case PERIPH_ID_SDMMC0: > case PERIPH_ID_SDMMC1: > src = readl(&clk->src_fsys); > - div = readl(&clk->div_fsys1); > + div = sub_div = readl(&clk->div_fsys1); > break; > case PERIPH_ID_SDMMC2: > case PERIPH_ID_SDMMC3: > src = readl(&clk->src_fsys); > - div = readl(&clk->div_fsys2); > + div = sub_div = readl(&clk->div_fsys2); > break; > case PERIPH_ID_I2C0: > case PERIPH_ID_I2C1: > @@ -422,12 +422,10 @@ static unsigned long exynos5_get_periph_rate(int peripheral) > case PERIPH_ID_I2C5: > case PERIPH_ID_I2C6: > case PERIPH_ID_I2C7: > - sclk = exynos5_get_pll_clk(MPLL); > - sub_div = ((readl(&clk->div_top1) >> bit_info->div_bit) > - & bit_info->div_mask) + 1; > - div = ((readl(&clk->div_top0) >> bit_info->prediv_bit) > - & bit_info->prediv_mask) + 1; > - return (sclk / sub_div) / div; > + src = EXYNOS_SRC_MPLL; > + div = readl(&clk->div_top0); > + sub_div = readl(&clk->div_top1); > + break; > default: > debug("%s: invalid peripheral %d", __func__, peripheral); > return -1; > @@ -446,29 +444,26 @@ static unsigned long exynos5_get_periph_rate(int peripheral) > case EXYNOS_SRC_VPLL: > sclk = exynos5_get_pll_clk(VPLL); > break; > - default: > - return 0; Why remove? I think it's better to use default label and also how about add debug log? > } > > - /* Ratio clock division for this peripheral */ > - if (bit_info->div_bit >= 0) { > - sub_div = (div >> bit_info->div_bit) & bit_info->div_mask; > - sub_clk = sclk / (sub_div + 1); > - } > + /* Clock divider ratio for this peripheral */ > + if (bit_info->div_bit >= 0) > + div = (div >> bit_info->div_bit) & bit_info->div_mask; > > - if (bit_info->prediv_bit >= 0) { > - div = (div >> bit_info->prediv_bit) & bit_info->prediv_mask; > - return sub_clk / (div + 1); > - } > + /* Clock pre-divider ratio for this peripheral */ > + if (bit_info->prediv_bit >= 0) > + sub_div = (sub_div >> bit_info->prediv_bit) > + & bit_info->prediv_mask; > > - return sub_clk; > + /* Calculate and return required clock rate */ > + return (sclk / (div + 1)) / (sub_div + 1); > } > > static unsigned long exynos542x_get_periph_rate(int peripheral) > { > struct clk_bit_info *bit_info = get_clk_bit_info(peripheral); > - unsigned long sclk, sub_clk = 0; > - unsigned int src, div, sub_div = 0; > + unsigned long sclk = 0; > + unsigned int src = 0, div = 0, sub_div = 0; > struct exynos5420_clock *clk = > (struct exynos5420_clock *)samsung_get_base_clock(); > > @@ -516,10 +511,9 @@ static unsigned long exynos542x_get_periph_rate(int peripheral) > case PERIPH_ID_I2C8: > case PERIPH_ID_I2C9: > case PERIPH_ID_I2C10: > - sclk = exynos542x_get_pll_clk(MPLL); > - sub_div = ((readl(&clk->div_top1) >> bit_info->div_bit) > - & bit_info->div_mask) + 1; > - return sclk / sub_div; > + src = EXYNOS542X_SRC_MPLL; > + div = readl(&clk->div_top1); > + break; > default: > debug("%s: invalid peripheral %d", __func__, peripheral); > return -1; > @@ -541,23 +535,19 @@ static unsigned long exynos542x_get_periph_rate(int peripheral) > case EXYNOS542X_SRC_RPLL: > sclk = exynos542x_get_pll_clk(RPLL); > break; > - default: > - return 0; Ditto. > } > > - /* Ratio clock division for this peripheral */ > - if (bit_info->div_bit >= 0) { > + /* Clock divider ratio for this peripheral */ > + if (bit_info->div_bit >= 0) > div = (div >> bit_info->div_bit) & bit_info->div_mask; > - sub_clk = sclk / (div + 1); > - } > > - if (bit_info->prediv_bit >= 0) { > + /* Clock pre-divider ratio for this peripheral */ > + if (bit_info->prediv_bit >= 0) > sub_div = (sub_div >> bit_info->prediv_bit) > - & bit_info->prediv_mask; > - return sub_clk / (sub_div + 1); > - } > + & bit_info->prediv_mask; > > - return sub_clk; > + /* Calculate and return required clock rate */ > + return (sclk / (div + 1)) / (sub_div + 1); > } > > unsigned long clock_get_periph_rate(int peripheral) > Thanks.
diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c index 3884d4b..8724bc7 100644 --- a/arch/arm/cpu/armv7/exynos/clock.c +++ b/arch/arm/cpu/armv7/exynos/clock.c @@ -366,8 +366,8 @@ static struct clk_bit_info *get_clk_bit_info(int peripheral) static unsigned long exynos5_get_periph_rate(int peripheral) { struct clk_bit_info *bit_info = get_clk_bit_info(peripheral); - unsigned long sclk, sub_clk = 0; - unsigned int src, div, sub_div = 0; + unsigned long sclk = 0; + unsigned int src = 0, div = 0, sub_div = 0; struct exynos5_clock *clk = (struct exynos5_clock *)samsung_get_base_clock(); @@ -389,30 +389,30 @@ static unsigned long exynos5_get_periph_rate(int peripheral) break; case PERIPH_ID_I2S0: src = readl(&clk->src_mau); - div = readl(&clk->div_mau); + div = sub_div = readl(&clk->div_mau); case PERIPH_ID_SPI0: case PERIPH_ID_SPI1: src = readl(&clk->src_peric1); - div = readl(&clk->div_peric1); + div = sub_div = readl(&clk->div_peric1); break; case PERIPH_ID_SPI2: src = readl(&clk->src_peric1); - div = readl(&clk->div_peric2); + div = sub_div = readl(&clk->div_peric2); break; case PERIPH_ID_SPI3: case PERIPH_ID_SPI4: src = readl(&clk->sclk_src_isp); - div = readl(&clk->sclk_div_isp); + div = sub_div = readl(&clk->sclk_div_isp); break; case PERIPH_ID_SDMMC0: case PERIPH_ID_SDMMC1: src = readl(&clk->src_fsys); - div = readl(&clk->div_fsys1); + div = sub_div = readl(&clk->div_fsys1); break; case PERIPH_ID_SDMMC2: case PERIPH_ID_SDMMC3: src = readl(&clk->src_fsys); - div = readl(&clk->div_fsys2); + div = sub_div = readl(&clk->div_fsys2); break; case PERIPH_ID_I2C0: case PERIPH_ID_I2C1: @@ -422,12 +422,10 @@ static unsigned long exynos5_get_periph_rate(int peripheral) case PERIPH_ID_I2C5: case PERIPH_ID_I2C6: case PERIPH_ID_I2C7: - sclk = exynos5_get_pll_clk(MPLL); - sub_div = ((readl(&clk->div_top1) >> bit_info->div_bit) - & bit_info->div_mask) + 1; - div = ((readl(&clk->div_top0) >> bit_info->prediv_bit) - & bit_info->prediv_mask) + 1; - return (sclk / sub_div) / div; + src = EXYNOS_SRC_MPLL; + div = readl(&clk->div_top0); + sub_div = readl(&clk->div_top1); + break; default: debug("%s: invalid peripheral %d", __func__, peripheral); return -1; @@ -446,29 +444,26 @@ static unsigned long exynos5_get_periph_rate(int peripheral) case EXYNOS_SRC_VPLL: sclk = exynos5_get_pll_clk(VPLL); break; - default: - return 0; } - /* Ratio clock division for this peripheral */ - if (bit_info->div_bit >= 0) { - sub_div = (div >> bit_info->div_bit) & bit_info->div_mask; - sub_clk = sclk / (sub_div + 1); - } + /* Clock divider ratio for this peripheral */ + if (bit_info->div_bit >= 0) + div = (div >> bit_info->div_bit) & bit_info->div_mask; - if (bit_info->prediv_bit >= 0) { - div = (div >> bit_info->prediv_bit) & bit_info->prediv_mask; - return sub_clk / (div + 1); - } + /* Clock pre-divider ratio for this peripheral */ + if (bit_info->prediv_bit >= 0) + sub_div = (sub_div >> bit_info->prediv_bit) + & bit_info->prediv_mask; - return sub_clk; + /* Calculate and return required clock rate */ + return (sclk / (div + 1)) / (sub_div + 1); } static unsigned long exynos542x_get_periph_rate(int peripheral) { struct clk_bit_info *bit_info = get_clk_bit_info(peripheral); - unsigned long sclk, sub_clk = 0; - unsigned int src, div, sub_div = 0; + unsigned long sclk = 0; + unsigned int src = 0, div = 0, sub_div = 0; struct exynos5420_clock *clk = (struct exynos5420_clock *)samsung_get_base_clock(); @@ -516,10 +511,9 @@ static unsigned long exynos542x_get_periph_rate(int peripheral) case PERIPH_ID_I2C8: case PERIPH_ID_I2C9: case PERIPH_ID_I2C10: - sclk = exynos542x_get_pll_clk(MPLL); - sub_div = ((readl(&clk->div_top1) >> bit_info->div_bit) - & bit_info->div_mask) + 1; - return sclk / sub_div; + src = EXYNOS542X_SRC_MPLL; + div = readl(&clk->div_top1); + break; default: debug("%s: invalid peripheral %d", __func__, peripheral); return -1; @@ -541,23 +535,19 @@ static unsigned long exynos542x_get_periph_rate(int peripheral) case EXYNOS542X_SRC_RPLL: sclk = exynos542x_get_pll_clk(RPLL); break; - default: - return 0; } - /* Ratio clock division for this peripheral */ - if (bit_info->div_bit >= 0) { + /* Clock divider ratio for this peripheral */ + if (bit_info->div_bit >= 0) div = (div >> bit_info->div_bit) & bit_info->div_mask; - sub_clk = sclk / (div + 1); - } - if (bit_info->prediv_bit >= 0) { + /* Clock pre-divider ratio for this peripheral */ + if (bit_info->prediv_bit >= 0) sub_div = (sub_div >> bit_info->prediv_bit) - & bit_info->prediv_mask; - return sub_clk / (sub_div + 1); - } + & bit_info->prediv_mask; - return sub_clk; + /* Calculate and return required clock rate */ + return (sclk / (div + 1)) / (sub_div + 1); } unsigned long clock_get_periph_rate(int peripheral)
Cleaning up soc_get_periph_rate to make the logic easy to comprehend. Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> --- Changes since v4: - New patch. arch/arm/cpu/armv7/exynos/clock.c | 76 +++++++++++++++++---------------------- 1 file changed, 33 insertions(+), 43 deletions(-)