Patrick Georgi (patrick@georgi-clan.de) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/4463
-gerrit
commit 21c908bf6280b4c52dc983f0deb25b3439f75b27 Author: David Hendricks dhendrix@chromium.org Date: Thu Aug 8 20:45:53 2013 -0700
exynos5420: re-factor clock_get_periph_rate()
This re-factors clock_get_periph_rate() to be a simpler and also make a few corrections along the way. To summarize:
- clk_bit_info is no longer used. It had numerous errors and was really painful anyway since it was just a bunch of opaque magic numbers that made bugs non-obvious.
- Clock source bitfields for peripherals handled in the switch statement are 3 bits, not 4. Some divider values are 3 bits, some are 4. The earlier code always assumed 4 bits for both which included reserved bits in many cases.
- UART source clock and divider shift values were wrong.
- PWM clock divider was being read from the wrong register.
- SPI3 divider value was being read from the wrong register.
- There was a really confusing calculation for SDMMC0 and SDMMC2 clock rates, but it was never actually used since the switch statement never handled PERIPH_ID_SDMMC{0,2} and would thus return if they were ever passed into this function.
Signed-off-by: David Hendricks dhendrix@chromium.org
Change-Id: I0a03a64d8b42fbe83dbf377292597ce681b22f4b Reviewed-on: https://gerrit.chromium.org/gerrit/65284 Commit-Queue: David Hendricks dhendrix@chromium.org Tested-by: David Hendricks dhendrix@chromium.org Reviewed-by: Gabe Black gabeblack@chromium.org --- src/cpu/samsung/exynos5420/clk.h | 10 ----- src/cpu/samsung/exynos5420/clock.c | 86 +++++++++++++++----------------------- 2 files changed, 33 insertions(+), 63 deletions(-)
diff --git a/src/cpu/samsung/exynos5420/clk.h b/src/cpu/samsung/exynos5420/clk.h index c5e7f58..3f97319 100644 --- a/src/cpu/samsung/exynos5420/clk.h +++ b/src/cpu/samsung/exynos5420/clk.h @@ -38,16 +38,6 @@ enum periph_id; #define DPLL 9 #define IPLL 10
-/* * - * This structure is to store the src bit, div bit and prediv bit - * positions of the peripheral clocks of the src and div registers - */ -struct clk_bit_info { - s8 src_bit; /* offset in register to clock source field */ - s8 div_bit; - s8 prediv_bit; -}; - unsigned long get_pll_clk(int pllreg); unsigned long get_arm_clk(void); unsigned long get_pwm_clk(void); diff --git a/src/cpu/samsung/exynos5420/clock.c b/src/cpu/samsung/exynos5420/clock.c index 82b1813..783679a 100644 --- a/src/cpu/samsung/exynos5420/clock.c +++ b/src/cpu/samsung/exynos5420/clock.c @@ -29,32 +29,6 @@ /* input clock of PLL: SMDK5420 has 24MHz input clock */ #define CONFIG_SYS_CLK_FREQ 24000000
-/* src_bit div_bit prediv_bit */ -static struct clk_bit_info clk_bit_info[PERIPH_ID_COUNT] = { - {0, 0, -1}, - {4, 4, -1}, - {8, 8, -1}, - {12, 12, -1}, - {0, 0, 8}, - {4, 16, 24}, - {8, 0, 8}, - {12, 16, 24}, - {-1, -1, -1}, - {16, 0, 8}, /* PERIPH_ID_SROMC */ - {20, 20, 24}, - {24, 24, 8}, - {28, 28, 4}, - {4, 12, 16}, - {-1, -1, -1}, - {-1, -1, -1}, - [PERIPH_ID_DPHPD] - {24, 0, -1}, - {24, 0, -1}, - {24, 0, -1}, - {24, 0, -1}, - {24, 0, -1}, -}; - /* Epll Clock division values to achive different frequency output */ static struct st_epll_con_val epll_div[] = { { 192000000, 0, 48, 3, 1, 0 }, @@ -197,37 +171,54 @@ static int clock_select_to_pll(enum peripheral_clock_select sel)
unsigned long clock_get_periph_rate(enum periph_id peripheral) { - struct clk_bit_info *bit_info = &clk_bit_info[peripheral]; - unsigned long sclk, sub_clk; - unsigned int src, div, sub_div; + unsigned long sclk; + unsigned int src, div; struct exynos5420_clock *clk = samsung_get_base_clock();
switch (peripheral) { case PERIPH_ID_UART0: + src = (readl(&clk->clk_src_peric0) >> 4) & 0x7; + div = (readl(&clk->clk_div_peric0) >> 8) & 0xf; + break; case PERIPH_ID_UART1: + src = (readl(&clk->clk_src_peric0) >> 8) & 0x7; + div = (readl(&clk->clk_div_peric0) >> 12) & 0xf; + break; case PERIPH_ID_UART2: + src = (readl(&clk->clk_src_peric0) >> 12) & 0x7; + div = (readl(&clk->clk_div_peric0) >> 16) & 0xf; + break; case PERIPH_ID_UART3: - src = readl(&clk->clk_src_peric0); - div = readl(&clk->clk_div_peric0); + src = (readl(&clk->clk_src_peric0) >> 16) & 0x7; + div = (readl(&clk->clk_div_peric0) >> 20) & 0xf; break; case PERIPH_ID_PWM0: case PERIPH_ID_PWM1: case PERIPH_ID_PWM2: case PERIPH_ID_PWM3: case PERIPH_ID_PWM4: - src = readl(&clk->clk_src_peric0); - div = readl(&clk->clk_div_peric3); + src = (readl(&clk->clk_src_peric0) >> 24) & 0x7; + div = (readl(&clk->clk_div_peric0) >> 28) & 0x7; break; case PERIPH_ID_SPI0: + src = (readl(&clk->clk_src_peric1) >> 20) & 0x7; + div = (readl(&clk->clk_div_peric1) >> 20) & 0xf; + break; case PERIPH_ID_SPI1: + src = (readl(&clk->clk_src_peric1) >> 24) & 0x7; + div = (readl(&clk->clk_div_peric1) >> 24) & 0xf; + break; case PERIPH_ID_SPI2: - src = readl(&clk->clk_src_peric1); - div = readl(&clk->clk_div_peric1); + src = (readl(&clk->clk_src_peric1) >> 28) & 0x7; + div = (readl(&clk->clk_div_peric1) >> 28) & 0xf; break; - case PERIPH_ID_SPI3: - case PERIPH_ID_SPI4: - src = readl(&clk->clk_src_isp); - div = readl(&clk->clk_div_isp1); + case PERIPH_ID_SPI3: /* aka SPI0_ISP */ + src = (readl(&clk->clk_src_isp) >> 16) & 0x7; + div = (readl(&clk->clk_div_isp0) >> 0) & 0x7; + break; + case PERIPH_ID_SPI4: /* aka SPI1_ISP */ + src = (readl(&clk->clk_src_isp) >> 12) & 0x7; + div = (readl(&clk->clk_div_isp1) >> 4) & 0x7; break; case PERIPH_ID_I2C0: case PERIPH_ID_I2C1: @@ -244,12 +235,11 @@ unsigned long clock_get_periph_rate(enum periph_id peripheral) div = ((readl(&clk->clk_div_top1) >> 8) & 0x3f) + 1; return sclk / div; default: - printk(BIOS_DEBUG, "%s: invalid peripheral %d", __func__, peripheral); + printk(BIOS_DEBUG, "%s: invalid peripheral %d", + __func__, peripheral); return -1; };
- src = (src >> bit_info->src_bit) & 0xf; - src = clock_select_to_pll(src); if (src < 0) { printk(BIOS_DEBUG, "%s: cannot determine source PLL", __func__); @@ -258,17 +248,7 @@ unsigned long clock_get_periph_rate(enum periph_id peripheral)
sclk = get_pll_clk(src);
- /* Ratio clock division for this peripheral */ - sub_div = (div >> bit_info->div_bit) & 0xf; - sub_clk = sclk / (sub_div + 1); - - /* Pre-ratio clock division for SDMMC0 and 2 */ - if (peripheral == PERIPH_ID_SDMMC0 || peripheral == PERIPH_ID_SDMMC2) { - div = (div >> bit_info->prediv_bit) & 0xff; - return sub_clk / (div + 1); - } - - return sub_clk; + return sclk / (div + 1); }
/* exynos5: return ARM clock frequency */