From: Janakarajan Natarajan Subject: [PATCH 2/2] Allow SEV firmware to be chosen based on Family and Model Date: Fri, 14 Sep 2018 17:32:04 -0500 Message-ID: <5c58c32c0ce89c35a95e151734f5d43a3ed0dca0.1536959537.git.Janakarajan.Natarajan@amd.com> References: Mime-Version: 1.0 Content-Type: text/plain Cc: Tom Lendacky , Gary Hook , Herbert Xu , "David S . Miller" , Brijesh Singh , Janakarajan Natarajan To: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org During PSP initialization, there is an attempt to update the SEV firmware by looking in /lib/firmware/amd/. Currently, sev.fw is the expected name of the firmware blob. This patch will allow for firmware filenames based on the family and model of the processor. Model specific firmware files are given highest priority. Followed by firmware for a subset of models. Lastly, failing the previous two options, fallback to looking for sev.fw. Signed-off-by: Janakarajan Natarajan --- drivers/crypto/ccp/psp-dev.c | 44 ++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 40 insertions(+), 4 deletions(-) diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index f541e60..3b33863 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -31,8 +31,9 @@ ((psp_master->api_major) >= _maj && \ (psp_master->api_minor) >= _min) -#define DEVICE_NAME "sev" -#define SEV_FW_FILE "amd/sev.fw" +#define DEVICE_NAME "sev" +#define SEV_FW_FILE "amd/sev.fw" +#define SEV_FW_NAME_SIZE 64 static DEFINE_MUTEX(sev_cmd_mutex); static struct sev_misc_dev *misc_dev; @@ -440,6 +441,40 @@ static int sev_get_api_version(void) return 0; } +int sev_get_firmware(struct device *dev, const struct firmware **firmware) +{ + char fw_name_specific[SEV_FW_NAME_SIZE]; + char fw_name_subset[SEV_FW_NAME_SIZE]; + + snprintf(fw_name_specific, sizeof(fw_name_specific), + "amd/amd_sev_fam%.2xh_model%.2xh.sbin", + boot_cpu_data.x86, boot_cpu_data.x86_model); + + snprintf(fw_name_subset, sizeof(fw_name_subset), + "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", + boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); + + /* Check for SEV FW for a particular model. + * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h + * + * or + * + * Check for SEV FW common to a subset of models. + * Ex. amd_sev_fam17h_model0xh.sbin for + * Family 17h Model 00h -- Family 17h Model 0Fh + * + * or + * + * Fall-back to using generic name: sev.fw + */ + if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || + (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || + (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) + return 0; + + return -ENOENT; +} + /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ static int sev_update_firmware(struct device *dev) { @@ -449,9 +484,10 @@ static int sev_update_firmware(struct device *dev) struct page *p; u64 data_size; - ret = request_firmware(&firmware, SEV_FW_FILE, dev); - if (ret < 0) + if (sev_get_firmware(dev, &firmware) == -ENOENT) { + dev_dbg(dev, "No SEV firmware file present\n"); return -1; + } /* * SEV FW expects the physical address given to it to be 32 -- 2.7.4