From: Xi Pardee Date: Fri, 25 Apr 2025 19:52:33 +0000 (-0700) Subject: platform/x86:intel/pmc: Improve pmc_core_get_lpm_req() X-Git-Tag: v6.16-rc1~125^2~44 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=a59211ee4610226251a723e9381a2c145a28fc4c;p=linux-2.6-block.git platform/x86:intel/pmc: Improve pmc_core_get_lpm_req() Minor improvements on pmc_core_get_lpm_req(). 1. Move the long comment to be above the function 2. Use %pe to print error pointer 3. Remove unneeded devm_kfree call These changes improves the code maintainability. Signed-off-by: Xi Pardee Link: https://lore.kernel.org/r/20250425195237.493129-6-xi.pardee@linux.intel.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c index 93a335b0ea63..a32adc53da98 100644 --- a/drivers/platform/x86/intel/pmc/core.c +++ b/drivers/platform/x86/intel/pmc/core.c @@ -1355,6 +1355,50 @@ static u32 pmc_core_find_guid(struct pmc_info *list, const struct pmc_reg_map *m return 0; } +/* + * This function retrieves low power mode requirement data from PMC Low + * Power Mode (LPM) table. + * + * In telemetry space, the LPM table contains a 4 byte header followed + * by 8 consecutive mode blocks (one for each LPM mode). Each block + * has a 4 byte header followed by a set of registers that describe the + * IP state requirements for the given mode. The IP mapping is platform + * specific but the same for each block, making for easy analysis. + * Platforms only use a subset of the space to track the requirements + * for their IPs. Callers provide the requirement registers they use as + * a list of indices. Each requirement register is associated with an + * IP map that's maintained by the caller. + * + * Header + * +----+----------------------------+----------------------------+ + * | 0 | REVISION | ENABLED MODES | + * +----+--------------+-------------+-------------+--------------+ + * + * Low Power Mode 0 Block + * +----+--------------+-------------+-------------+--------------+ + * | 1 | SUB ID | SIZE | MAJOR | MINOR | + * +----+--------------+-------------+-------------+--------------+ + * | 2 | LPM0 Requirements 0 | + * +----+---------------------------------------------------------+ + * | | ... | + * +----+---------------------------------------------------------+ + * | 29 | LPM0 Requirements 27 | + * +----+---------------------------------------------------------+ + * + * ... + * + * Low Power Mode 7 Block + * +----+--------------+-------------+-------------+--------------+ + * | | SUB ID | SIZE | MAJOR | MINOR | + * +----+--------------+-------------+-------------+--------------+ + * | 60 | LPM7 Requirements 0 | + * +----+---------------------------------------------------------+ + * | | ... | + * +----+---------------------------------------------------------+ + * | 87 | LPM7 Requirements 27 | + * +----+---------------------------------------------------------+ + * + */ static int pmc_core_get_lpm_req(struct pmc_dev *pmcdev, struct pmc *pmc, struct pci_dev *pcidev) { struct telem_endpoint *ep; @@ -1374,8 +1418,7 @@ static int pmc_core_get_lpm_req(struct pmc_dev *pmcdev, struct pmc *pmc, struct ep = pmt_telem_find_and_register_endpoint(pcidev, guid, 0); if (IS_ERR(ep)) { - dev_dbg(&pmcdev->pdev->dev, "couldn't get telem endpoint %ld", - PTR_ERR(ep)); + dev_dbg(&pmcdev->pdev->dev, "couldn't get telem endpoint %pe", ep); return -EPROBE_DEFER; } @@ -1387,49 +1430,6 @@ static int pmc_core_get_lpm_req(struct pmc_dev *pmcdev, struct pmc *pmc, struct goto unregister_ep; } - /* - * PMC Low Power Mode (LPM) table - * - * In telemetry space, the LPM table contains a 4 byte header followed - * by 8 consecutive mode blocks (one for each LPM mode). Each block - * has a 4 byte header followed by a set of registers that describe the - * IP state requirements for the given mode. The IP mapping is platform - * specific but the same for each block, making for easy analysis. - * Platforms only use a subset of the space to track the requirements - * for their IPs. Callers provide the requirement registers they use as - * a list of indices. Each requirement register is associated with an - * IP map that's maintained by the caller. - * - * Header - * +----+----------------------------+----------------------------+ - * | 0 | REVISION | ENABLED MODES | - * +----+--------------+-------------+-------------+--------------+ - * - * Low Power Mode 0 Block - * +----+--------------+-------------+-------------+--------------+ - * | 1 | SUB ID | SIZE | MAJOR | MINOR | - * +----+--------------+-------------+-------------+--------------+ - * | 2 | LPM0 Requirements 0 | - * +----+---------------------------------------------------------+ - * | | ... | - * +----+---------------------------------------------------------+ - * | 29 | LPM0 Requirements 27 | - * +----+---------------------------------------------------------+ - * - * ... - * - * Low Power Mode 7 Block - * +----+--------------+-------------+-------------+--------------+ - * | | SUB ID | SIZE | MAJOR | MINOR | - * +----+--------------+-------------+-------------+--------------+ - * | 60 | LPM7 Requirements 0 | - * +----+---------------------------------------------------------+ - * | | ... | - * +----+---------------------------------------------------------+ - * | 87 | LPM7 Requirements 27 | - * +----+---------------------------------------------------------+ - * - */ mode_offset = LPM_HEADER_OFFSET + LPM_MODE_OFFSET; pmc_for_each_mode(mode, pmcdev) { u32 *req_offset = pmc->lpm_req_regs + (mode * num_maps); @@ -1442,7 +1442,6 @@ static int pmc_core_get_lpm_req(struct pmc_dev *pmcdev, struct pmc *pmc, struct if (ret) { dev_err(&pmcdev->pdev->dev, "couldn't read Low Power Mode requirements: %d\n", ret); - devm_kfree(&pmcdev->pdev->dev, pmc->lpm_req_regs); goto unregister_ep; } ++req_offset;