mediatek/mt8183: Initialize DRAM with a sequence in constant array

The DRAM init sequence is simply setting some values on register
for all DRAM modules, no logic involved;
so we can replace it by an array to configure easily.

BUG=b:80501386
BRANCH=none
TEST=Boots correctly on Kukui, and inits DRAM successfully with related
     patches.

Change-Id: Iacd3ce909ba7a0bdf699c5bfcb2b97f383d7bb6f
Signed-off-by: Huayang Duan <huayang.duan@mediatek.com>
Reviewed-on: https://review.coreboot.org/28836
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>

src/soc/mediatek/mt8183/Makefile.inc

@@ -21,6 +21,7 @@ verstage-$(CONFIG_DRIVERS_UART) += ../common/uart.c
 verstage-y += ../common/wdt.c
 
 romstage-y += ../common/cbmem.c emi.c
+romstage-y += dramc_init_setting.c
 romstage-y += memory.c
 romstage-y += ../common/gpio.c gpio.c
 romstage-y += ../common/mmu_operations.c mmu_operations.c

src/soc/mediatek/mt8183/emi.c

@@ -281,6 +281,7 @@ static void init_dram(const struct sdram_params *params)
 	dramc_set_broadcast(DRAMC_BROADCAST_ON);
 	dramc_init_pre_settings();
 
+	dramc_init();
 	emi_init2(params);
 }
 

src/soc/mediatek/mt8183/include/soc/dramc_pi_api.h

@@ -132,4 +132,5 @@ enum {
 void dramc_get_rank_size(u64 *dram_rank_size);
 void dramc_set_broadcast(u32 onoff);
 u32 dramc_get_broadcast(void);
+void dramc_init(void);
 #endif /* _DRAMC_PI_API_MT8183_H */