From d3b077e2b6329ea1d6e36d8abc56b8740a9e79d7 Mon Sep 17 00:00:00 2001 From: Felix Held Date: Mon, 6 Mar 2023 23:31:40 +0100 Subject: soc/amd/common/block/acpi/cpu_power_state: add get_cstate_info helper Introduce the get_cstate_info helper function that populates the caller- provided cstate_values array with the data returned by the SoC-specific get_cstate_config_data function. From the array get_cstate_config_data returns, only the ctype, latency and power fields are used, so the rest can be left uninitialized. Those 3 fields are compile-time constants. For each entry, write_cstate_entry will generate the corresponding resource information from the given data. In the C1 case where ctype is 1, the state is entered via a MWAIT instruction, while the higher C states are entered by doing an IO read from a specific IO address. This IO address is x - 1 bytes into the IO region starting at MSR_CSTATE_ADDRESS for the Cx state. So for example C2 is entered by reading from the C state IO base address + 1. This resource information is generated during runtime, since the contents of MSR_CSTATE_ADDRESS aren't necessarily known at compile-time. MAX_CSTATE_COUNT is introduced so that the caller can allocate and pass a buffer with space for the maximum number of C state entries. This maximum number corresponds to the number of IO addresses the CPU traps beginning from MSR_CSTATE_ADDRESS. In practice, it's unlikely that more than 3 or maybe 4 C states will be available though. Signed-off-by: Felix Held Change-Id: I2c36c1d604ced349c609882b9d9fe84d5f726a8d Reviewed-on: https://review.coreboot.org/c/coreboot/+/73428 Tested-by: build bot (Jenkins) Reviewed-by: Fred Reitberger Reviewed-by: Eric Lai --- src/soc/amd/common/block/acpi/Kconfig | 3 ++ src/soc/amd/common/block/acpi/Makefile.inc | 1 + src/soc/amd/common/block/acpi/cpu_power_state.c | 65 ++++++++++++++++++++++++ src/soc/amd/common/block/include/amdblocks/cpu.h | 8 +++ 4 files changed, 77 insertions(+) create mode 100644 src/soc/amd/common/block/acpi/cpu_power_state.c (limited to 'src') diff --git a/src/soc/amd/common/block/acpi/Kconfig b/src/soc/amd/common/block/acpi/Kconfig index 46251d6c40..039fed8868 100644 --- a/src/soc/amd/common/block/acpi/Kconfig +++ b/src/soc/amd/common/block/acpi/Kconfig @@ -18,6 +18,9 @@ config SOC_AMD_COMMON_BLOCK_ACPI_DPTC config SOC_AMD_COMMON_BLOCK_ACPI_CPPC bool +config SOC_AMD_COMMON_BLOCK_ACPI_CPU_POWER_STATE + bool + config SOC_AMD_COMMON_BLOCK_ACPI_GPIO bool diff --git a/src/soc/amd/common/block/acpi/Makefile.inc b/src/soc/amd/common/block/acpi/Makefile.inc index 2c8f391889..cf1e9c1a14 100644 --- a/src/soc/amd/common/block/acpi/Makefile.inc +++ b/src/soc/amd/common/block/acpi/Makefile.inc @@ -13,6 +13,7 @@ ramstage-y += tables.c ramstage-$(CONFIG_ACPI_BERT) += bert.c ramstage-$(CONFIG_SOC_AMD_COMMON_BLOCK_ACPI_ALIB) += alib.c ramstage-$(CONFIG_SOC_AMD_COMMON_BLOCK_ACPI_CPPC) += cppc.c +ramstage-$(CONFIG_SOC_AMD_COMMON_BLOCK_ACPI_CPU_POWER_STATE) += cpu_power_state.c ramstage-$(CONFIG_SOC_AMD_COMMON_BLOCK_ACPI_GPIO) += gpio.c ramstage-$(CONFIG_SOC_AMD_COMMON_BLOCK_ACPI_IVRS) += ivrs.c diff --git a/src/soc/amd/common/block/acpi/cpu_power_state.c b/src/soc/amd/common/block/acpi/cpu_power_state.c new file mode 100644 index 0000000000..d8af0c9244 --- /dev/null +++ b/src/soc/amd/common/block/acpi/cpu_power_state.c @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include +#include +#include +#include +#include +#include +#include + +static void write_cstate_entry(acpi_cstate_t *entry, const acpi_cstate_t *data, + uint32_t cstate_io_base_address) +{ + if (!data->ctype) { + printk(BIOS_WARNING, "Invalid C-state data; skipping entry.\n"); + return; + } + + entry->ctype = data->ctype; + entry->latency = data->latency; + entry->power = data->power; + + if (data->ctype == 1) { + entry->resource = (acpi_addr_t){ + .space_id = ACPI_ADDRESS_SPACE_FIXED, + .bit_width = 2, + .bit_offset = 2, + .addrl = 0, + .addrh = 0, + }; + } else { + entry->resource = (acpi_addr_t){ + .space_id = ACPI_ADDRESS_SPACE_IO, + .bit_width = 8, + .bit_offset = 0, + /* ctype is 1-indexed while the offset into cstate_io_base_address is + 0-indexed */ + .addrl = cstate_io_base_address + data->ctype - 1, + .addrh = 0, + .access_size = ACPI_ACCESS_SIZE_BYTE_ACCESS, + }; + } +} + +size_t get_cstate_info(acpi_cstate_t *cstate_values) +{ + size_t i; + size_t cstate_count; + uint32_t cstate_io_base_address = + rdmsr(MSR_CSTATE_ADDRESS).lo & MSR_CSTATE_ADDRESS_MASK; + const acpi_cstate_t *cstate_config = get_cstate_config_data(&cstate_count); + + if (cstate_count > MAX_CSTATE_COUNT) { + printk(BIOS_WARNING, "cstate_info array has too many entries. " + "Skipping last %zu entries.\n", + cstate_count - MAX_CSTATE_COUNT); + cstate_count = MAX_CSTATE_COUNT; + } + + for (i = 0; i < cstate_count; i++) { + write_cstate_entry(&cstate_values[i], &cstate_config[i], cstate_io_base_address); + } + + return i; +} diff --git a/src/soc/amd/common/block/include/amdblocks/cpu.h b/src/soc/amd/common/block/include/amdblocks/cpu.h index de3fb84d12..a380a2df93 100644 --- a/src/soc/amd/common/block/include/amdblocks/cpu.h +++ b/src/soc/amd/common/block/include/amdblocks/cpu.h @@ -3,10 +3,18 @@ #ifndef AMD_BLOCK_CPU_H #define AMD_BLOCK_CPU_H +#include +#include + +#define MAX_CSTATE_COUNT 8 + void early_cache_setup(void); int get_cpu_count(void); unsigned int get_threads_per_core(void); void set_cstate_io_addr(void); void write_resume_eip(void); +size_t get_cstate_info(acpi_cstate_t *cstate_values); +const acpi_cstate_t *get_cstate_config_data(size_t *size); + #endif /* AMD_BLOCK_CPU_H */ -- cgit v1.2.3