soc/mediatek/mt8192: Do memory pll init before calibration

Memory PLL is used to provide the basic clock for dram controller
and DDRPHY. PLL must be initialized as predefined way.
First, enable PLL POWER and ISO, wait at least 30us, release ISO, then
configure PLL frequency and enable PLL master switch.
At last, enable control ability for SPM to switch between active and
idle when system is switched between normal and low power mode.

TEST=Confirm Memory PLL frequency is right by frequency meter

Signed-off-by: Huayang Duan <huayang.duan@mediatek.com>
Change-Id: Ieb4e6cbf19da53d653872b166d3191c7b010dca6
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44702
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Frans Hendriks <fhendriks@eltan.com>

2 files changed, 30 insertions, 0 deletions

diff --git a/src/soc/mediatek/mt8192/dramc_pi_main.c b/src/soc/mediatek/mt8192/dramc_pi_main.c
index a2a4dea1c4..cdb598fcc5 100644
--- a/src/soc/mediatek/mt8192/dramc_pi_main.c
+++ b/src/soc/mediatek/mt8192/dramc_pi_main.c
@@ -2,6 +2,8 @@
 
 #include <soc/dramc_pi_api.h>
 #include <soc/dramc_register.h>
+#include <soc/pll.h>
+#include <soc/pll_common.h>
 #include <soc/regulator.h>
 
 static void set_vcore_voltage(const struct ddr_cali *cali)
@@ -16,6 +18,25 @@ static void dramc_calibration_all_channels(struct ddr_cali *cali)
 {
 }
 
+static void mem_pll_init(void)
+{
+	SET32_BITFIELDS(&mtk_apmixed->mpll_con3, PLL_POWER_ISO_ENABLE, 3);
+
+	udelay(30);
+	SET32_BITFIELDS(&mtk_apmixed->mpll_con3, PLL_ISO_ENABLE, 0);
+
+	udelay(1);
+	SET32_BITFIELDS(&mtk_apmixed->mpll_con1, PLL_CON1, MPLL_CON1_FREQ);
+	SET32_BITFIELDS(&mtk_apmixed->mpll_con0, PLL_ENABLE, 1);
+
+	udelay(20);
+	SET32_BITFIELDS(&mtk_apmixed->pllon_con0, MPLL_IOS_SEL, 0);
+	SET32_BITFIELDS(&mtk_apmixed->pllon_con0, MPLL_EN_SEL, 0);
+	SET32_BITFIELDS(&mtk_apmixed->pllon_con1, MPLL_PWR_SEL, 0);
+	SET32_BITFIELDS(&mtk_apmixed->pllon_con2, MPLL_BY_ISO_DLY, 0);
+	SET32_BITFIELDS(&mtk_apmixed->pllon_con3, MPLL_BY_PWR_DLY, 0);
+}
+
 void init_dram(const struct dramc_data *dparam)
 {
 	u32 bc_bak;
@@ -35,6 +56,7 @@ void init_dram(const struct dramc_data *dparam)
 	cali.emi_config = &ddr_info->emi_config;
 
 	dramc_set_broadcast(DRAMC_BROADCAST_ON);
+	mem_pll_init();
 
 	global_option_init(&cali);
 	bc_bak = dramc_get_broadcast();
diff --git a/src/soc/mediatek/mt8192/include/soc/pll.h b/src/soc/mediatek/mt8192/include/soc/pll.h
index 52bf3c2f38..cd1c01250c 100644
--- a/src/soc/mediatek/mt8192/include/soc/pll.h
+++ b/src/soc/mediatek/mt8192/include/soc/pll.h
@@ -241,6 +241,8 @@ check_member(mtk_apmixed_regs, ap_pllgp1_con0, 0x0200);
 check_member(mtk_apmixed_regs, ap_pllgp2_con0, 0x0300);
 check_member(mtk_apmixed_regs, usbpll_con2, 0x03cc);
 
+#define MPLL_CON1_FREQ		0x84200000
+
 enum {
 	USBPLL_EN = 0x1 << 2,
 
@@ -306,6 +308,12 @@ DEFINE_BITFIELD(CLK_MISC_CFG_0_METER_DIV, 31, 24)
 DEFINE_BITFIELD(CLK26CALI_0_TRIGGER, 4, 4)
 DEFINE_BITFIELD(CLK26CALI_1_LOAD_CNT, 25, 16)
 
+DEFINE_BIT(MPLL_IOS_SEL, 2)
+DEFINE_BIT(MPLL_EN_SEL, 11)
+DEFINE_BIT(MPLL_PWR_SEL, 20)
+DEFINE_BIT(MPLL_BY_ISO_DLY, 2)
+DEFINE_BIT(MPLL_BY_PWR_DLY, 2)
+
 DEFINE_BITFIELD(WDT_SWSYSRST_KEY, 31, 24)
 DEFINE_BITFIELD(WDT_SWSYSRST_CONN_MCU, 12, 12)