exynos/snow: Move core/memory clock-related and board ID code

This patch moves ARM core and DRAM timing functions around to simplify
the dependencies for system_clock_init().

The original code was architected such that the system_clock_init()
function called other functions to obtain core and memory timings.
Due to the way memory timing information must be obtained on Snow,
which entails decoding platform-specific board straps, the bottom-
up approach resulted in having the low-level clock init code
implicitly depend on board and vendor-specific info:

main()
  ->system_clock_init()
    -> get_arm_ratios()
       -> CPU-specific code
    -> clock_get_mem_timings()
       -> board_get_revision()
          -> read GPIOs (3-state logic)
          -> Decode GPIOs in a vendor-specific manner
       -> Choose memory timings from module-specific look-up table
  ...then proceed to init clocks
...come back to main()

The new approach gathers all board and vendor-specific info in a
more appropriate location and passes it into system_clock_init():
main()
  -> get_arm_ratios()
     -> CPU-specific code
  -> get_mem_timings()
     -> board_get_config()
        -> read GPIOs (3-state logic)
        -> Decode GPIOs in a vendor-specific manner
     -> Choose memory timings from module-specific look-up table
  -> system_clock_init()
...back to main()

Change-Id: Ie237ebff76fc2d8a4d2f4577a226ac3909e4d4e8
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2271
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 109 insertions, 4 deletions

diff --git a/src/cpu/samsung/exynos5250/clock.c b/src/cpu/samsung/exynos5250/clock.c
index 0250d77a28..fc01387125 100644
--- a/src/cpu/samsung/exynos5250/clock.c
+++ b/src/cpu/samsung/exynos5250/clock.c
@@ -26,17 +26,107 @@
 #include <stdlib.h>
 //#include <fdtdec.h>
 #include <arch/io.h>
-//#include <asm/arch/clock.h>
-//#include <asm/arch/clk.h>
-#include <cpu/samsung/exynos5-common/clk.h>
 #include <cpu/samsung/exynos5250/clk.h>
+#include <cpu/samsung/exynos5250/clock_init.h>
 #include <cpu/samsung/exynos5250/cpu.h>
-#include <cpu/samsung/exynos5250/periph.h>
 #include <cpu/samsung/s5p-common/clk.h>
 
 /* input clock of PLL: SMDK5250 has 24MHz input clock */
 #define CONFIG_SYS_CLK_FREQ            24000000
 
+struct arm_clk_ratios arm_clk_ratios[] = {
+	{
+		.arm_freq_mhz = 600,
+
+		.apll_mdiv = 0xc8,
+		.apll_pdiv = 0x4,
+		.apll_sdiv = 0x1,
+
+		.arm2_ratio = 0x0,
+		.apll_ratio = 0x1,
+		.pclk_dbg_ratio = 0x1,
+		.atb_ratio = 0x2,
+		.periph_ratio = 0x7,
+		.acp_ratio = 0x7,
+		.cpud_ratio = 0x1,
+		.arm_ratio = 0x0,
+	}, {
+		.arm_freq_mhz = 800,
+
+		.apll_mdiv = 0x64,
+		.apll_pdiv = 0x3,
+		.apll_sdiv = 0x0,
+
+		.arm2_ratio = 0x0,
+		.apll_ratio = 0x1,
+		.pclk_dbg_ratio = 0x1,
+		.atb_ratio = 0x3,
+		.periph_ratio = 0x7,
+		.acp_ratio = 0x7,
+		.cpud_ratio = 0x2,
+		.arm_ratio = 0x0,
+	}, {
+		.arm_freq_mhz = 1000,
+
+		.apll_mdiv = 0x7d,
+		.apll_pdiv = 0x3,
+		.apll_sdiv = 0x0,
+
+		.arm2_ratio = 0x0,
+		.apll_ratio = 0x1,
+		.pclk_dbg_ratio = 0x1,
+		.atb_ratio = 0x4,
+		.periph_ratio = 0x7,
+		.acp_ratio = 0x7,
+		.cpud_ratio = 0x2,
+		.arm_ratio = 0x0,
+	}, {
+		.arm_freq_mhz = 1200,
+
+		.apll_mdiv = 0x96,
+		.apll_pdiv = 0x3,
+		.apll_sdiv = 0x0,
+
+		.arm2_ratio = 0x0,
+		.apll_ratio = 0x3,
+		.pclk_dbg_ratio = 0x1,
+		.atb_ratio = 0x5,
+		.periph_ratio = 0x7,
+		.acp_ratio = 0x7,
+		.cpud_ratio = 0x3,
+		.arm_ratio = 0x0,
+	}, {
+		.arm_freq_mhz = 1400,
+
+		.apll_mdiv = 0xaf,
+		.apll_pdiv = 0x3,
+		.apll_sdiv = 0x0,
+
+		.arm2_ratio = 0x0,
+		.apll_ratio = 0x3,
+		.pclk_dbg_ratio = 0x1,
+		.atb_ratio = 0x6,
+		.periph_ratio = 0x7,
+		.acp_ratio = 0x7,
+		.cpud_ratio = 0x3,
+		.arm_ratio = 0x0,
+	}, {
+		.arm_freq_mhz = 1700,
+
+		.apll_mdiv = 0x1a9,
+		.apll_pdiv = 0x6,
+		.apll_sdiv = 0x0,
+
+		.arm2_ratio = 0x0,
+		.apll_ratio = 0x3,
+		.pclk_dbg_ratio = 0x1,
+		.atb_ratio = 0x6,
+		.periph_ratio = 0x7,
+		.acp_ratio = 0x7,
+		.cpud_ratio = 0x3,
+		.arm_ratio = 0x0,
+	}
+};
 
 /* src_bit div_bit prediv_bit */
 static struct clk_bit_info clk_bit_info[PERIPH_ID_COUNT] = {
@@ -269,6 +359,21 @@ unsigned long get_arm_clk(void)
 	return armclk;
 }
 
+struct arm_clk_ratios *get_arm_clk_ratios(void)
+{
+	struct arm_clk_ratios *arm_ratio;
+	unsigned long arm_freq = 1700;	/* FIXME: use get_arm_clk() */
+	int i;
+
+	for (i = 0, arm_ratio = arm_clk_ratios; i < ARRAY_SIZE(arm_clk_ratios);
+		i++, arm_ratio++) {
+		if (arm_ratio->arm_freq_mhz == arm_freq)
+			return arm_ratio;
+	}
+
+	return NULL;
+}
+
 /* exynos5: set the mmc clock */
 void set_mmc_clk(int dev_index, unsigned int div)
 {