From 428131364f0073a18682a5d3ee9cf13d8042cfce Mon Sep 17 00:00:00 2001 From: Gayatri Kammela Date: Fri, 16 Apr 2021 20:12:48 -0700 Subject: [PATCH] platform/x86: intel_pmc_core: Get LPM requirements for Tiger Lake Platforms that support low power modes (LPM) such as Tiger Lake maintain requirements for each sub-state that a readable in the PMC. However, unlike LPM status registers, requirement registers are not memory mapped but are available from an ACPI _DSM. Collect the requirements for Tiger Lake using the _DSM method and store in a buffer. Signed-off-by: Gayatri Kammela Co-developed-by: David E. Box Signed-off-by: David E. Box Reviewed-by: Hans de Goede Link: https://lore.kernel.org/r/20210417031252.3020837-6-david.e.box@linux.intel.com Signed-off-by: Hans de Goede --- drivers/platform/x86/intel_pmc_core.c | 56 +++++++++++++++++++++++++++++++++++ drivers/platform/x86/intel_pmc_core.h | 2 ++ 2 files changed, 58 insertions(+) diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c index 0e59a84..bafb0d9 100644 --- a/drivers/platform/x86/intel_pmc_core.c +++ b/drivers/platform/x86/intel_pmc_core.c @@ -23,7 +23,9 @@ #include #include #include +#include +#include #include #include #include @@ -31,6 +33,9 @@ #include "intel_pmc_core.h" +#define ACPI_S0IX_DSM_UUID "57a6512e-3979-4e9d-9708-ff13b2508972" +#define ACPI_GET_LOW_MODE_REGISTERS 1 + /* PKGC MSRs are common across Intel Core SoCs */ static const struct pmc_bit_map msr_map[] = { {"Package C2", MSR_PKG_C2_RESIDENCY}, @@ -590,6 +595,53 @@ static const struct pmc_reg_map tgl_reg_map = { .etr3_offset = ETR3_OFFSET, }; +static void pmc_core_get_tgl_lpm_reqs(struct platform_device *pdev) +{ + struct pmc_dev *pmcdev = platform_get_drvdata(pdev); + const int num_maps = pmcdev->map->lpm_num_maps; + u32 lpm_size = LPM_MAX_NUM_MODES * num_maps * 4; + union acpi_object *out_obj; + struct acpi_device *adev; + guid_t s0ix_dsm_guid; + u32 *lpm_req_regs, *addr; + + adev = ACPI_COMPANION(&pdev->dev); + if (!adev) + return; + + guid_parse(ACPI_S0IX_DSM_UUID, &s0ix_dsm_guid); + + out_obj = acpi_evaluate_dsm(adev->handle, &s0ix_dsm_guid, 0, + ACPI_GET_LOW_MODE_REGISTERS, NULL); + if (out_obj && out_obj->type == ACPI_TYPE_BUFFER) { + u32 size = out_obj->buffer.length; + + if (size != lpm_size) { + acpi_handle_debug(adev->handle, + "_DSM returned unexpected buffer size, have %u, expect %u\n", + size, lpm_size); + goto free_acpi_obj; + } + } else { + acpi_handle_debug(adev->handle, + "_DSM function 0 evaluation failed\n"); + goto free_acpi_obj; + } + + addr = (u32 *)out_obj->buffer.pointer; + + lpm_req_regs = devm_kzalloc(&pdev->dev, lpm_size * sizeof(u32), + GFP_KERNEL); + if (!lpm_req_regs) + goto free_acpi_obj; + + memcpy(lpm_req_regs, addr, lpm_size); + pmcdev->lpm_req_regs = lpm_req_regs; + +free_acpi_obj: + ACPI_FREE(out_obj); +} + static inline u32 pmc_core_reg_read(struct pmc_dev *pmcdev, int reg_offset) { return readl(pmcdev->regbase + reg_offset); @@ -1424,10 +1476,14 @@ static int pmc_core_probe(struct platform_device *pdev) return -ENOMEM; mutex_init(&pmcdev->lock); + pmcdev->pmc_xram_read_bit = pmc_core_check_read_lock_bit(pmcdev); pmc_core_get_low_power_modes(pmcdev); pmc_core_do_dmi_quirks(pmcdev); + if (pmcdev->map == &tgl_reg_map) + pmc_core_get_tgl_lpm_reqs(pdev); + /* * On TGL, due to a hardware limitation, the GBE LTR blocks PC10 when * a cable is attached. Tell the PMC to ignore it. diff --git a/drivers/platform/x86/intel_pmc_core.h b/drivers/platform/x86/intel_pmc_core.h index aa44fd5..64fb368 100644 --- a/drivers/platform/x86/intel_pmc_core.h +++ b/drivers/platform/x86/intel_pmc_core.h @@ -294,6 +294,7 @@ struct pmc_reg_map { * @s0ix_counter: S0ix residency (step adjusted) * @num_lpm_modes: Count of enabled modes * @lpm_en_modes: Array of enabled modes from lowest to highest priority + * @lpm_req_regs: List of substate requirements * * pmc_dev contains info about power management controller device. */ @@ -310,6 +311,7 @@ struct pmc_dev { u64 s0ix_counter; int num_lpm_modes; int lpm_en_modes[LPM_MAX_NUM_MODES]; + u32 *lpm_req_regs; }; #define pmc_for_each_mode(i, mode, pmcdev) \ -- 2.7.4