From 2183484e7aefdd576d01342ba4a7db74b480e8a3 Mon Sep 17 00:00:00 2001 From: Jianjun Wang Date: Fri, 25 Feb 2022 09:36:45 +0800 Subject: mb/google/cherry: Pre-initialize PCIe at the bootblock stage Described in PCIe CEM specification sections 2.2 (PERST# Signal) and 2.2.1 (Initial Power-Up (G3 to S0)). The deassertion of PERST# should be delayed 100ms (TPVPERL) for the power and clock to become stable. Instead of asserting PERST# right before PCIe initialization and waiting for 100ms, which is currently the only function of 'mtk_pcie_pre_init', so that the extra 100ms delay in ramstage is avoided. TEST=Build pass and boot up to kernel successfully via SSD on Dojo board, here is the SSD information in boot log: == NVME IDENTIFY CONTROLLER DATA == PCI VID : 0x15b7 PCI SSVID : 0x15b7 SN : 21517J440114 MN : WDC PC SN530 SDBPTPZ-256G-1006 RAB : 0x4 AERL : 0x7 SQES : 0x66 CQES : 0x44 NN : 0x1 Identified NVMe model WDC PC SN530 SDBPTPZ-256G-1006 BUG=b:178565024 BRANCH=cherry Signed-off-by: Jianjun Wang Change-Id: Id5b9369e6f8599f93415588ea585c952a41c5e7d Reviewed-on: https://review.coreboot.org/c/coreboot/+/62359 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Yu-Ping Wu --- src/mainboard/google/cherry/bootblock.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'src/mainboard/google/cherry/bootblock.c') diff --git a/src/mainboard/google/cherry/bootblock.c b/src/mainboard/google/cherry/bootblock.c index c506cafc27..c811c4eb2e 100644 --- a/src/mainboard/google/cherry/bootblock.c +++ b/src/mainboard/google/cherry/bootblock.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include "gpio.h" @@ -43,6 +44,13 @@ static void usb3_hub_reset(void) void bootblock_mainboard_init(void) { + /* + * Initialize PCIe pinmux and assert PERST# early to reduce + * the impact of 100ms delay. + */ + if (CONFIG(PCI)) + mtk_pcie_pre_init(); + mtk_i2c_bus_init(CONFIG_DRIVER_TPM_I2C_BUS, I2C_SPEED_FAST); mtk_spi_init(CONFIG_EC_GOOGLE_CHROMEEC_SPI_BUS, SPI_PAD0_MASK, 3 * MHz, 0); nor_set_gpio_pinmux(); -- cgit v1.2.3