From 3406dd64c328bf0f2f1902d42b239f84c136e4f0 Mon Sep 17 00:00:00 2001 From: Furquan Shaikh Date: Fri, 4 Aug 2017 15:58:26 -0700 Subject: soc/intel/common/uart: Refactor uart_common_init 1. Create a new function uart_lpss_init which takes the UART LPSS controller out of reset and initializes and enables clock. 2. Instead of passing in m/n clock divider values as parameters to uart_common_init, introduce Kconfig variables so that uart_lpss_init can use the values directly without having to query the SoC. BUG=b:64030366 TEST=Verified that UART still works on APL and KBL boards. Change-Id: I74d01b0037d8c38fe6480c38ff2283d76097282a Signed-off-by: Furquan Shaikh Reviewed-on: https://review.coreboot.org/20884 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin --- src/soc/intel/apollolake/Kconfig | 10 ++++++++++ src/soc/intel/apollolake/include/soc/uart.h | 7 ------- src/soc/intel/apollolake/uart_early.c | 2 +- src/soc/intel/common/block/include/intelblocks/uart.h | 8 ++++++-- src/soc/intel/common/block/uart/Kconfig | 12 ++++++++++++ src/soc/intel/common/block/uart/uart.c | 18 ++++++++++++------ src/soc/intel/skylake/Kconfig | 9 +++++++++ src/soc/intel/skylake/bootblock/uart.c | 6 +----- 8 files changed, 51 insertions(+), 21 deletions(-) (limited to 'src/soc') diff --git a/src/soc/intel/apollolake/Kconfig b/src/soc/intel/apollolake/Kconfig index cc516f32ad..1323f573d1 100644 --- a/src/soc/intel/apollolake/Kconfig +++ b/src/soc/intel/apollolake/Kconfig @@ -351,4 +351,14 @@ config APL_SKIP_SET_POWER_LIMITS Limits (RAPL) algorithm for a constant power management. Set this config option to skip the RAPL configuration. +# M and N divisor values for clock frequency configuration. +# These values get us a 1.836 MHz clock (ideally we want 1.843 MHz) +config SOC_INTEL_COMMON_LPSS_UART_CLK_M_VAL + hex + default 0x25a + +config SOC_INTEL_COMMON_LPSS_UART_CLK_N_VAL + hex + default 0x7fff + endif diff --git a/src/soc/intel/apollolake/include/soc/uart.h b/src/soc/intel/apollolake/include/soc/uart.h index b2b1bb8623..bf8b9d74e3 100644 --- a/src/soc/intel/apollolake/include/soc/uart.h +++ b/src/soc/intel/apollolake/include/soc/uart.h @@ -18,13 +18,6 @@ #ifndef _SOC_APOLLOLAKE_UART_H_ #define _SOC_APOLLOLAKE_UART_H_ -/* -* M and N divisor values for clock frequency configuration. -* These values get us a 1.836 MHz clock (ideally we want 1.843 MHz) -*/ -#define CLK_M_VAL 0x025a -#define CLK_N_VAL 0x7fff - /* Initialize the console UART including the pads for the configured UART. */ void pch_uart_init(void); diff --git a/src/soc/intel/apollolake/uart_early.c b/src/soc/intel/apollolake/uart_early.c index 4c143ad854..d3c1b0d0ca 100644 --- a/src/soc/intel/apollolake/uart_early.c +++ b/src/soc/intel/apollolake/uart_early.c @@ -69,6 +69,6 @@ void pch_uart_init(void) gpio_configure_pads(&uart_gpios[pad_index * 2], 2); /* Program UART2 BAR0, command, reset and clock register */ - uart_common_init(uart, base, CLK_M_VAL, CLK_N_VAL); + uart_common_init(uart, base); } diff --git a/src/soc/intel/common/block/include/intelblocks/uart.h b/src/soc/intel/common/block/include/intelblocks/uart.h index b46edd76d7..9ec5004e08 100644 --- a/src/soc/intel/common/block/include/intelblocks/uart.h +++ b/src/soc/intel/common/block/include/intelblocks/uart.h @@ -19,8 +19,12 @@ #include #include -void uart_common_init(device_t dev, uintptr_t baseaddr, - uint32_t clk_m_val, uint32_t clk_n_val); +/* + * Common routine to initialize UART controller PCI config space, take it out of + * reset and configure M/N dividers. + */ +void uart_common_init(device_t dev, uintptr_t baseaddr); + void pch_uart_read_resources(struct device *dev); diff --git a/src/soc/intel/common/block/uart/Kconfig b/src/soc/intel/common/block/uart/Kconfig index 103659f4c4..f4a0e4e4b9 100644 --- a/src/soc/intel/common/block/uart/Kconfig +++ b/src/soc/intel/common/block/uart/Kconfig @@ -3,3 +3,15 @@ config SOC_INTEL_COMMON_BLOCK_UART select SOC_INTEL_COMMON_BLOCK_LPSS help Intel Processor common UART support + +config SOC_INTEL_COMMON_BLOCK_UART_LPSS_CLK_M_VAL + depends on SOC_INTEL_COMMON_BLOCK_UART + hex + help + Clock m-divisor value for m/n divider + +config SOC_INTEL_COMMON_BLOCK_UART_LPSS_CLK_N_VAL + depends on SOC_INTEL_COMMON_BLOCK_UART + hex + help + Clock m-divisor value for m/n divider diff --git a/src/soc/intel/common/block/uart/uart.c b/src/soc/intel/common/block/uart/uart.c index e8f1bc8094..be30464b13 100644 --- a/src/soc/intel/common/block/uart/uart.c +++ b/src/soc/intel/common/block/uart/uart.c @@ -19,8 +19,17 @@ #include #include -void uart_common_init(device_t dev, uintptr_t baseaddr, uint32_t clk_m_val, - uint32_t clk_n_val) +static void uart_lpss_init(uintptr_t baseaddr) +{ + /* Take UART out of reset */ + lpss_reset_release(baseaddr); + + /* Set M and N divisor inputs and enable clock */ + lpss_clk_update(baseaddr, CONFIG_SOC_INTEL_COMMON_LPSS_UART_CLK_M_VAL, + CONFIG_SOC_INTEL_COMMON_LPSS_UART_CLK_N_VAL); +} + +void uart_common_init(device_t dev, uintptr_t baseaddr) { /* Set UART base address */ pci_write_config32(dev, PCI_BASE_ADDRESS_0, baseaddr); @@ -29,11 +38,8 @@ void uart_common_init(device_t dev, uintptr_t baseaddr, uint32_t clk_m_val, pci_write_config32(dev, PCI_COMMAND, PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER); - /* Take UART out of reset */ - lpss_reset_release(baseaddr); + uart_lpss_init(baseaddr); - /* Set M and N divisor inputs and enable clock */ - lpss_clk_update(baseaddr, clk_m_val, clk_n_val); } #if ENV_RAMSTAGE diff --git a/src/soc/intel/skylake/Kconfig b/src/soc/intel/skylake/Kconfig index 32c2654c4d..f0402a9e2b 100644 --- a/src/soc/intel/skylake/Kconfig +++ b/src/soc/intel/skylake/Kconfig @@ -317,4 +317,13 @@ config CPU_BCLK_MHZ int default 100 +# Clock divider parameters for 115200 baud rate +config SOC_INTEL_COMMON_LPSS_UART_CLK_M_VAL + hex + default 0x30 + +config SOC_INTEL_COMMON_LPSS_UART_CLK_N_VAL + hex + default 0xc35 + endif diff --git a/src/soc/intel/skylake/bootblock/uart.c b/src/soc/intel/skylake/bootblock/uart.c index 26b81c0589..b7ab241f77 100644 --- a/src/soc/intel/skylake/bootblock/uart.c +++ b/src/soc/intel/skylake/bootblock/uart.c @@ -31,10 +31,6 @@ #define PCR_SIO_PCH_LEGACY_UART1 (1 << 1) #define PCR_SIO_PCH_LEGACY_UART2 (1 << 2) -/* Clock divider parameters for 115200 baud rate */ -#define CLK_M_VAL 0x30 -#define CLK_N_VAL 0xc35 - /* UART2 pad configuration. Support RXD and TXD for now. */ static const struct pad_config uart2_pads[] = { /* UART2_RXD */ PAD_CFG_NF(GPP_C20, NONE, DEEP, NF1), @@ -45,7 +41,7 @@ void pch_uart_init(void) { uintptr_t base = uart_platform_base(CONFIG_UART_FOR_CONSOLE); - uart_common_init(PCH_DEV_UART2, base, CLK_M_VAL, CLK_N_VAL); + uart_common_init(PCH_DEV_UART2, base); /* Put UART2 in byte access mode for 16550 compatibility */ if (!IS_ENABLED(CONFIG_DRIVERS_UART_8250MEM_32)) -- cgit v1.2.3