Change in coreboot[master]: google/grunt: Reset BayHub EMMC freq to SD base CLK 50MHz

[Kevin Chiu (Code Review)]

Kevin Chiu has uploaded this change for review. ( https://review.coreboot.org/28353

Change subject: google/grunt: Reset BayHub EMMC freq to SD base CLK 50MHz
......................................................................

google/grunt: Reset BayHub EMMC freq to SD base CLK 50MHz

Bayhub eMMC controller default runs SD base 50MHz at the first power on.
After boot into OS, mmc kernel driver will config controller to HS200/208MHz
and send MMC CMD21 (tuning block).
But Bayhub PCR register 0x3E4[22] (eMMC MODE select) is not clear
after system warn reset.
So eMMC will still run 208Mhz but there is no block tuning cmd in depthcharge.
It will cause two Sandisk eMMC (SDINBDA4-64G-V/SDINBDA4-32G-V) failing to
load kernel and trap in 0x5B error (No bootable kernel found on disk).

BUG=b:111964336
BRANCH=master
TEST=emerge-grunt coreboot
Change-Id: Ic080682e67323577c7f0ba4ed08f8adafca620cc
Signed-off-by: Kevin Chiu 
---
M src/drivers/generic/bayhub/bh720.c
M src/drivers/generic/bayhub/bh720.h
M src/mainboard/google/kahlee/variants/baseboard/mainboard.c
3 files changed, 43 insertions(+), 4 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/53/28353/1

diff --git a/src/drivers/generic/bayhub/bh720.c b/src/drivers/generic/bayhub/bh720.c
index b689b67..0441683 100644
--- a/src/drivers/generic/bayhub/bh720.c
+++ b/src/drivers/generic/bayhub/bh720.c
@@ -23,7 +23,7 @@
 #include "chip.h"
 #include "bh720.h"

-__attribute__((weak)) void bh720_driving_strength(struct device *dev)
+__attribute__((weak)) void board_bh720(struct device *dev)
 {
 }

@@ -55,7 +55,7 @@
    	       pci_read_config32(dev, BH720_LINK_CTRL));
    }

-	bh720_driving_strength(dev);
+	board_bh720(dev);
 }

static struct pci_operations pci_ops = {
diff --git a/src/drivers/generic/bayhub/bh720.h b/src/drivers/generic/bayhub/bh720.h
index b6fd273..3a4b3b6 100644
--- a/src/drivers/generic/bayhub/bh720.h
+++ b/src/drivers/generic/bayhub/bh720.h
@@ -35,13 +35,20 @@

BH720_MEM_RW_DATA               = 0x200,
    BH720_MEM_RW_ADR                = 0x204,
+	BH720_MEM_RW_READ		= BIT(30),
+	BH720_MEM_RW_WRITE		= BIT(31),
    BH720_MEM_ACCESS_EN             = 0x208,
-	BH720_PCR                       = 0x304,
+	BH720_PCR_DrvStrength_PLL	= 0x304,
    BH720_PCR_DATA_CMD_DRV_MAX      = 7,
    BH720_PCR_CLK_DRV_MAX           = 7,
+	BH720_PCR_EMMC_SETTING		= 0x308,
+	BH720_PCR_EMMC_SETTING_1_8V	= BIT(4),

BH720_RTD3_L1                   = 0x3e0,
    BH720_RTD3_L1_DISABLE_L1        = BIT(28),
+
+	BH720_PCR_CSR			= 0x3e4,
+	BH720_PCR_CSR_EMMC_MODE_SEL	= BIT(22),
 };

-void bh720_driving_strength(struct device *dev);
+void board_bh720(struct device *dev);
diff --git a/src/mainboard/google/kahlee/variants/baseboard/mainboard.c b/src/mainboard/google/kahlee/variants/baseboard/mainboard.c
index cf38b99..252829e 100644
--- a/src/mainboard/google/kahlee/variants/baseboard/mainboard.c
+++ b/src/mainboard/google/kahlee/variants/baseboard/mainboard.c
@@ -17,6 +17,8 @@
 #include <baseboard/variants.h>
 #include <gpio.h>
 #include <variant/gpio.h>
+#include <device/pci.h>
+#include <drivers/generic/bayhub/bh720.h>

uint8_t variant_board_sku(void)
 {
@@ -35,3 +37,33 @@
    gpio_set(GPIO_133, 0);
 }
 #endif
+
+void board_bh720(struct device *dev)
+{
+	u32 sdbar;
+	u32 bh720_pcr_data;
+
+	sdbar = pci_read_config32(dev, PCI_BASE_ADDRESS_1);
+
+	/* Enable Memory Access Function */
+	write32((void *)(sdbar + BH720_MEM_ACCESS_EN), 0x40000000);
+	write32((void *)(sdbar + BH720_MEM_RW_DATA), 0x80000000);
+	write32((void *)(sdbar + BH720_MEM_RW_ADR), 0x800000D0);
+
+	// Set EMMC VCCQ 1.8V PCR 0x308[4]
+	write32((void *)(sdbar + BH720_MEM_RW_ADR), BH720_MEM_RW_READ | BH720_PCR_EMMC_SETTING);
+	bh720_pcr_data = read32((void *)(sdbar + BH720_MEM_RW_DATA));
+	write32((void *)(sdbar + BH720_MEM_RW_DATA), bh720_pcr_data | BH720_PCR_EMMC_SETTING_1_8V);
+	write32((void *)(sdbar + BH720_MEM_RW_ADR), BH720_MEM_RW_WRITE | BH720_PCR_EMMC_SETTING);
+
+	// Set Bayhub SD base CLK 50MHz: case#1 PCR 0x3E4[22] = 0
+	write32((void *)(sdbar + BH720_MEM_RW_ADR), BH720_MEM_RW_READ | BH720_PCR_CSR);
+	bh720_pcr_data = read32((void *)(sdbar + BH720_MEM_RW_DATA));
+	write32((void *)(sdbar + BH720_MEM_RW_DATA), bh720_pcr_data & ~BH720_PCR_CSR_EMMC_MODE_SEL);
+	write32((void *)(sdbar + BH720_MEM_RW_ADR), BH720_MEM_RW_WRITE | BH720_PCR_CSR);
+
+	/* Disable Memroy Access */
+	write32((void *)(sdbar + BH720_MEM_RW_DATA), 0x80000001);
+	write32((void *)(sdbar + BH720_MEM_RW_ADR), 0x800000D0);
+	write32((void *)(sdbar + BH720_MEM_ACCESS_EN), 0x80000000);
+}