From 9a434cee773ae15309ac225f27551b5492618e4a Mon Sep 17 00:00:00 2001 From: Elliot Berman Date: Tue, 7 Jan 2020 13:04:26 -0800 Subject: [PATCH] firmware: qcom_scm: Dynamically support SMCCC and legacy conventions Dynamically support SMCCCC and legacy conventions by detecting which convention to use at runtime. qcom_scm_call_atomic and qcom_scm_call can then be moved in qcom_scm.c and use underlying convention backend as appropriate. Thus, rename qcom_scm-64,-32 to reflect that they are backends for -smc and -legacy, respectively. Also add support for making SCM calls earlier than when SCM driver probes to support use cases such as qcom_scm_set_cold_boot_addr. Support is added by lazily initializing the convention and guarding the query with a spin lock. The limitation of these early SCM calls is that they cannot use DMA, as in the case of >4 arguments for SMC convention and any non-atomic call for legacy convention. Tested-by: Brian Masney # arm32 Tested-by: Stephan Gerhold Signed-off-by: Elliot Berman Link: https://lore.kernel.org/r/1578431066-19600-18-git-send-email-eberman@codeaurora.org Signed-off-by: Bjorn Andersson --- drivers/firmware/Kconfig | 8 - drivers/firmware/Makefile | 4 +- .../{qcom_scm-32.c => qcom_scm-legacy.c} | 31 +--- .../{qcom_scm-64.c => qcom_scm-smc.c} | 95 +----------- drivers/firmware/qcom_scm.c | 146 +++++++++++++++++- drivers/firmware/qcom_scm.h | 27 +++- 6 files changed, 176 insertions(+), 135 deletions(-) rename drivers/firmware/{qcom_scm-32.c => qcom_scm-legacy.c} (90%) rename drivers/firmware/{qcom_scm-64.c => qcom_scm-smc.c} (57%) diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index e40a77bfe821..ea869addc89b 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -239,14 +239,6 @@ config QCOM_SCM depends on ARM || ARM64 select RESET_CONTROLLER -config QCOM_SCM_32 - def_bool y - depends on QCOM_SCM && ARM - -config QCOM_SCM_64 - def_bool y - depends on QCOM_SCM && ARM64 - config QCOM_SCM_DOWNLOAD_MODE_DEFAULT bool "Qualcomm download mode enabled by default" depends on QCOM_SCM diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 747fb73b264c..e9fb838af4df 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -17,9 +17,7 @@ obj-$(CONFIG_ISCSI_IBFT) += iscsi_ibft.o obj-$(CONFIG_FIRMWARE_MEMMAP) += memmap.o obj-$(CONFIG_RASPBERRYPI_FIRMWARE) += raspberrypi.o obj-$(CONFIG_FW_CFG_SYSFS) += qemu_fw_cfg.o -obj-$(CONFIG_QCOM_SCM) += qcom_scm.o -obj-$(CONFIG_QCOM_SCM_64) += qcom_scm-64.o -obj-$(CONFIG_QCOM_SCM_32) += qcom_scm-32.o +obj-$(CONFIG_QCOM_SCM) += qcom_scm.o qcom_scm-smc.o qcom_scm-legacy.o obj-$(CONFIG_TI_SCI_PROTOCOL) += ti_sci.o obj-$(CONFIG_TRUSTED_FOUNDATIONS) += trusted_foundations.o obj-$(CONFIG_TURRIS_MOX_RWTM) += turris-mox-rwtm.o diff --git a/drivers/firmware/qcom_scm-32.c b/drivers/firmware/qcom_scm-legacy.c similarity index 90% rename from drivers/firmware/qcom_scm-32.c rename to drivers/firmware/qcom_scm-legacy.c index 08220e7f2167..8532e7c78ef7 100644 --- a/drivers/firmware/qcom_scm-32.c +++ b/drivers/firmware/qcom_scm-legacy.c @@ -26,7 +26,6 @@ struct arm_smccc_args { unsigned long args[8]; }; -#define SCM_LEGACY_FNID(s, c) (((s) << 10) | ((c) & 0x3ff)) /** * struct scm_legacy_command - one SCM command buffer @@ -129,8 +128,8 @@ static void __scm_legacy_do(const struct arm_smccc_args *smc, * and response buffers is taken care of by qcom_scm_call; however, callers are * responsible for any other cached buffers passed over to the secure world. */ -int qcom_scm_call(struct device *dev, const struct qcom_scm_desc *desc, - struct qcom_scm_res *res) +int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc, + struct qcom_scm_res *res) { u8 arglen = desc->arginfo & 0xf; int ret = 0, context_id; @@ -218,9 +217,9 @@ out: * This shall only be used with commands that are guaranteed to be * uninterruptable, atomic and SMP safe. */ -int qcom_scm_call_atomic(struct device *unused, - const struct qcom_scm_desc *desc, - struct qcom_scm_res *res) +int scm_legacy_call_atomic(struct device *unused, + const struct qcom_scm_desc *desc, + struct qcom_scm_res *res) { int context_id; struct arm_smccc_res smc_res; @@ -241,23 +240,3 @@ int qcom_scm_call_atomic(struct device *unused, return smc_res.a0; } - -int __qcom_scm_is_call_available(struct device *dev, u32 svc_id, u32 cmd_id) -{ - int ret; - struct qcom_scm_desc desc = { - .svc = QCOM_SCM_SVC_INFO, - .cmd = QCOM_SCM_INFO_IS_CALL_AVAIL, - .args[0] = SCM_LEGACY_FNID(svc_id, cmd_id), - .arginfo = QCOM_SCM_ARGS(1), - }; - struct qcom_scm_res res; - - ret = qcom_scm_call(dev, &desc, &res); - - return ret ? : res.result[0]; -} - -void __qcom_scm_init(void) -{ -} diff --git a/drivers/firmware/qcom_scm-64.c b/drivers/firmware/qcom_scm-smc.c similarity index 57% rename from drivers/firmware/qcom_scm-64.c rename to drivers/firmware/qcom_scm-smc.c index 4defc7c6f4cd..497c13ba98d6 100644 --- a/drivers/firmware/qcom_scm-64.c +++ b/drivers/firmware/qcom_scm-smc.c @@ -14,8 +14,6 @@ #include "qcom_scm.h" -#define SCM_SMC_FNID(s, c) ((((s) & 0xFF) << 8) | ((c) & 0xFF)) - /** * struct arm_smccc_args * @args: The array of values used in registers in smc instruction @@ -24,7 +22,6 @@ struct arm_smccc_args { unsigned long args[8]; }; -static u64 qcom_smccc_convention = -1; static DEFINE_MUTEX(qcom_scm_lock); #define QCOM_SCM_EBUSY_WAIT_MS 30 @@ -80,8 +77,8 @@ static void __scm_smc_do(const struct arm_smccc_args *smc, } while (res->a0 == QCOM_SCM_V2_EBUSY); } -static int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc, - struct qcom_scm_res *res, bool atomic) +int scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc, + struct qcom_scm_res *res, bool atomic) { int arglen = desc->arginfo & 0xf; int i; @@ -90,6 +87,9 @@ static int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc, size_t alloc_len; gfp_t flag = atomic ? GFP_ATOMIC : GFP_KERNEL; u32 smccc_call_type = atomic ? ARM_SMCCC_FAST_CALL : ARM_SMCCC_STD_CALL; + u32 qcom_smccc_convention = + (qcom_scm_convention == SMC_CONVENTION_ARM_32) ? + ARM_SMCCC_SMC_32 : ARM_SMCCC_SMC_64; struct arm_smccc_res smc_res; struct arm_smccc_args smc = {0}; @@ -149,88 +149,3 @@ static int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc, return (long)smc_res.a0 ? qcom_scm_remap_error(smc_res.a0) : 0; } - -/** - * qcom_scm_call() - Invoke a syscall in the secure world - * @dev: device - * @svc_id: service identifier - * @cmd_id: command identifier - * @desc: Descriptor structure containing arguments and return values - * - * Sends a command to the SCM and waits for the command to finish processing. - * This should *only* be called in pre-emptible context. - */ -int qcom_scm_call(struct device *dev, const struct qcom_scm_desc *desc, - struct qcom_scm_res *res) -{ - might_sleep(); - return __scm_smc_call(dev, desc, res, false); -} - -/** - * qcom_scm_call_atomic() - atomic variation of qcom_scm_call() - * @dev: device - * @svc_id: service identifier - * @cmd_id: command identifier - * @desc: Descriptor structure containing arguments and return values - * @res: Structure containing results from SMC/HVC call - * - * Sends a command to the SCM and waits for the command to finish processing. - * This can be called in atomic context. - */ -int qcom_scm_call_atomic(struct device *dev, const struct qcom_scm_desc *desc, - struct qcom_scm_res *res) -{ - return __scm_smc_call(dev, desc, res, true); -} - -int __qcom_scm_is_call_available(struct device *dev, u32 svc_id, u32 cmd_id) -{ - int ret; - struct qcom_scm_desc desc = { - .svc = QCOM_SCM_SVC_INFO, - .cmd = QCOM_SCM_INFO_IS_CALL_AVAIL, - .owner = ARM_SMCCC_OWNER_SIP, - }; - struct qcom_scm_res res; - - desc.arginfo = QCOM_SCM_ARGS(1); - desc.args[0] = SCM_SMC_FNID(svc_id, cmd_id) | - (ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT); - - ret = qcom_scm_call(dev, &desc, &res); - - return ret ? : res.result[0]; -} - -void __qcom_scm_init(void) -{ - struct qcom_scm_desc desc = { - .svc = QCOM_SCM_SVC_INFO, - .cmd = QCOM_SCM_INFO_IS_CALL_AVAIL, - .args[0] = SCM_SMC_FNID(QCOM_SCM_SVC_INFO, - QCOM_SCM_INFO_IS_CALL_AVAIL) | - (ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT), - .arginfo = QCOM_SCM_ARGS(1), - .owner = ARM_SMCCC_OWNER_SIP, - }; - struct qcom_scm_res res; - int ret; - - qcom_smccc_convention = ARM_SMCCC_SMC_64; - // Device isn't required as there is only one argument - no device - // needed to dma_map_single to secure world - ret = qcom_scm_call_atomic(NULL, &desc, &res); - if (!ret && res.result[0] == 1) - goto out; - - qcom_smccc_convention = ARM_SMCCC_SMC_32; - ret = qcom_scm_call_atomic(NULL, &desc, &res); - if (!ret && res.result[0] == 1) - goto out; - - qcom_smccc_convention = -1; - BUG(); -out: - pr_info("QCOM SCM SMC Convention: %lld\n", qcom_smccc_convention); -} diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c index 895f14830e32..059bb0fbae9e 100644 --- a/drivers/firmware/qcom_scm.c +++ b/drivers/firmware/qcom_scm.c @@ -72,6 +72,13 @@ static struct qcom_scm_wb_entry qcom_scm_wb[] = { { .flag = QCOM_SCM_FLAG_WARMBOOT_CPU3 }, }; +static const char *qcom_scm_convention_names[] = { + [SMC_CONVENTION_UNKNOWN] = "unknown", + [SMC_CONVENTION_ARM_32] = "smc arm 32", + [SMC_CONVENTION_ARM_64] = "smc arm 64", + [SMC_CONVENTION_LEGACY] = "smc legacy", +}; + static struct qcom_scm *__scm; static int qcom_scm_clk_enable(void) @@ -107,6 +114,143 @@ static void qcom_scm_clk_disable(void) clk_disable_unprepare(__scm->bus_clk); } +static int __qcom_scm_is_call_available(struct device *dev, u32 svc_id, + u32 cmd_id); + +enum qcom_scm_convention qcom_scm_convention; +static bool has_queried __read_mostly; +static DEFINE_SPINLOCK(query_lock); + +static void __query_convention(void) +{ + unsigned long flags; + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_INFO, + .cmd = QCOM_SCM_INFO_IS_CALL_AVAIL, + .args[0] = SCM_SMC_FNID(QCOM_SCM_SVC_INFO, + QCOM_SCM_INFO_IS_CALL_AVAIL) | + (ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT), + .arginfo = QCOM_SCM_ARGS(1), + .owner = ARM_SMCCC_OWNER_SIP, + }; + struct qcom_scm_res res; + int ret; + + spin_lock_irqsave(&query_lock, flags); + if (has_queried) + goto out; + + qcom_scm_convention = SMC_CONVENTION_ARM_64; + // Device isn't required as there is only one argument - no device + // needed to dma_map_single to secure world + ret = scm_smc_call(NULL, &desc, &res, true); + if (!ret && res.result[0] == 1) + goto out; + + qcom_scm_convention = SMC_CONVENTION_ARM_32; + ret = scm_smc_call(NULL, &desc, &res, true); + if (!ret && res.result[0] == 1) + goto out; + + qcom_scm_convention = SMC_CONVENTION_LEGACY; +out: + has_queried = true; + spin_unlock_irqrestore(&query_lock, flags); + pr_info("qcom_scm: convention: %s\n", + qcom_scm_convention_names[qcom_scm_convention]); +} + +static inline enum qcom_scm_convention __get_convention(void) +{ + if (unlikely(!has_queried)) + __query_convention(); + return qcom_scm_convention; +} + +/** + * qcom_scm_call() - Invoke a syscall in the secure world + * @dev: device + * @svc_id: service identifier + * @cmd_id: command identifier + * @desc: Descriptor structure containing arguments and return values + * + * Sends a command to the SCM and waits for the command to finish processing. + * This should *only* be called in pre-emptible context. + */ +static int qcom_scm_call(struct device *dev, const struct qcom_scm_desc *desc, + struct qcom_scm_res *res) +{ + might_sleep(); + switch (__get_convention()) { + case SMC_CONVENTION_ARM_32: + case SMC_CONVENTION_ARM_64: + return scm_smc_call(dev, desc, res, false); + case SMC_CONVENTION_LEGACY: + return scm_legacy_call(dev, desc, res); + default: + pr_err("Unknown current SCM calling convention.\n"); + return -EINVAL; + } +} + +/** + * qcom_scm_call_atomic() - atomic variation of qcom_scm_call() + * @dev: device + * @svc_id: service identifier + * @cmd_id: command identifier + * @desc: Descriptor structure containing arguments and return values + * @res: Structure containing results from SMC/HVC call + * + * Sends a command to the SCM and waits for the command to finish processing. + * This can be called in atomic context. + */ +static int qcom_scm_call_atomic(struct device *dev, + const struct qcom_scm_desc *desc, + struct qcom_scm_res *res) +{ + switch (__get_convention()) { + case SMC_CONVENTION_ARM_32: + case SMC_CONVENTION_ARM_64: + return scm_smc_call(dev, desc, res, true); + case SMC_CONVENTION_LEGACY: + return scm_legacy_call_atomic(dev, desc, res); + default: + pr_err("Unknown current SCM calling convention.\n"); + return -EINVAL; + } +} + +static int __qcom_scm_is_call_available(struct device *dev, u32 svc_id, + u32 cmd_id) +{ + int ret; + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_INFO, + .cmd = QCOM_SCM_INFO_IS_CALL_AVAIL, + .owner = ARM_SMCCC_OWNER_SIP, + }; + struct qcom_scm_res res; + + desc.arginfo = QCOM_SCM_ARGS(1); + switch (__get_convention()) { + case SMC_CONVENTION_ARM_32: + case SMC_CONVENTION_ARM_64: + desc.args[0] = SCM_SMC_FNID(svc_id, cmd_id) | + (ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT); + break; + case SMC_CONVENTION_LEGACY: + desc.args[0] = SCM_LEGACY_FNID(svc_id, cmd_id); + break; + default: + pr_err("Unknown SMC convention being used\n"); + return -EINVAL; + } + + ret = qcom_scm_call(dev, &desc, &res); + + return ret ? : res.result[0]; +} + /** * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus * @entry: Entry point function for the cpus @@ -971,7 +1115,7 @@ static int qcom_scm_probe(struct platform_device *pdev) __scm = scm; __scm->dev = &pdev->dev; - __qcom_scm_init(); + __query_convention(); /* * If requested enable "download mode", from this point on warmboot diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h index 9b7b3577821c..d9ed670da222 100644 --- a/drivers/firmware/qcom_scm.h +++ b/drivers/firmware/qcom_scm.h @@ -3,6 +3,16 @@ */ #ifndef __QCOM_SCM_INT_H #define __QCOM_SCM_INT_H + +enum qcom_scm_convention { + SMC_CONVENTION_UNKNOWN, + SMC_CONVENTION_LEGACY, + SMC_CONVENTION_ARM_32, + SMC_CONVENTION_ARM_64, +}; + +extern enum qcom_scm_convention qcom_scm_convention; + #define MAX_QCOM_SCM_ARGS 10 #define MAX_QCOM_SCM_RETS 3 @@ -50,11 +60,16 @@ struct qcom_scm_res { u64 result[MAX_QCOM_SCM_RETS]; }; -extern int qcom_scm_call(struct device *dev, const struct qcom_scm_desc *desc, - struct qcom_scm_res *res); -extern int qcom_scm_call_atomic(struct device *dev, - const struct qcom_scm_desc *desc, - struct qcom_scm_res *res); +#define SCM_SMC_FNID(s, c) ((((s) & 0xFF) << 8) | ((c) & 0xFF)) +extern int scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc, + struct qcom_scm_res *res, bool atomic); + +#define SCM_LEGACY_FNID(s, c) (((s) << 10) | ((c) & 0x3ff)) +extern int scm_legacy_call_atomic(struct device *dev, + const struct qcom_scm_desc *desc, + struct qcom_scm_res *res); +extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc, + struct qcom_scm_res *res); #define QCOM_SCM_SVC_BOOT 0x01 #define QCOM_SCM_BOOT_SET_ADDR 0x01 @@ -77,8 +92,6 @@ extern int qcom_scm_call_atomic(struct device *dev, #define QCOM_SCM_SVC_INFO 0x06 #define QCOM_SCM_INFO_IS_CALL_AVAIL 0x01 -extern int __qcom_scm_is_call_available(struct device *dev, u32 svc_id, - u32 cmd_id); #define QCOM_SCM_SVC_MP 0x0c #define QCOM_SCM_MP_RESTORE_SEC_CFG 0x02