Add the support of signed firmware using new TEE remoteproc device to manage a remote firmware in a secure trusted application.
The support of a signed or a non signed firmware is based on compatible: - with legacy compatible "st,stm32mp1-m4" the Linux kernel loads a non-signed (ELF) firmware image, - with compatible "st,stm32mp1-m4-tee" the Linux kernel load a signed firmware image. In this case it calls TEE services to manage the firmware loading and the remoteproc life-cycle.
Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@foss.st.com --- drivers/remoteproc/Kconfig | 1 + drivers/remoteproc/stm32_rproc.c | 234 ++++++++++++++++++++++++++----- 2 files changed, 198 insertions(+), 37 deletions(-)
diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig index 2969f067e3c3..e6f0ca4adf8a 100644 --- a/drivers/remoteproc/Kconfig +++ b/drivers/remoteproc/Kconfig @@ -316,6 +316,7 @@ config STM32_RPROC depends on ARCH_STM32 depends on REMOTEPROC select MAILBOX + select TEE_REMOTEPROC help Say y here to support STM32 MCU processors via the remote processor framework. diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c index 8746cbb1f168..d2c909905cba 100644 --- a/drivers/remoteproc/stm32_rproc.c +++ b/drivers/remoteproc/stm32_rproc.c @@ -20,6 +20,7 @@ #include <linux/remoteproc.h> #include <linux/reset.h> #include <linux/slab.h> +#include <linux/tee_remoteproc.h> #include <linux/workqueue.h>
#include "remoteproc_internal.h" @@ -49,6 +50,13 @@ #define M4_STATE_STANDBY 4 #define M4_STATE_CRASH 5
+/* + * Define a default index in future may come a global list of + * firmwares which list platforms and associated firmware(s) + */ + +#define STM32_MP1_FW_ID 0 + struct stm32_syscon { struct regmap *map; u32 reg; @@ -89,6 +97,8 @@ struct stm32_rproc { struct stm32_mbox mb[MBOX_NB_MBX]; struct workqueue_struct *workqueue; bool secured_soc; + bool fw_loaded; + struct tee_rproc *trproc; void __iomem *rsc_va; };
@@ -208,6 +218,139 @@ static int stm32_rproc_mbox_idx(struct rproc *rproc, const unsigned char *name) return -EINVAL; }
+static void stm32_rproc_request_shutdown(struct rproc *rproc) +{ + struct stm32_rproc *ddata = rproc->priv; + int err, dummy_data, idx; + + /* Request shutdown of the remote processor */ + if (rproc->state != RPROC_OFFLINE && rproc->state != RPROC_CRASHED) { + idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN); + if (idx >= 0 && ddata->mb[idx].chan) { + /* A dummy data is sent to allow to block on transmit. */ + err = mbox_send_message(ddata->mb[idx].chan, + &dummy_data); + if (err < 0) + dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n"); + } + } +} + +static int stm32_rproc_release(struct rproc *rproc) +{ + struct stm32_rproc *ddata = rproc->priv; + unsigned int err = 0; + + /* To allow platform Standby power mode, set remote proc Deep Sleep. */ + if (ddata->pdds.map) { + err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg, + ddata->pdds.mask, 1); + if (err) { + dev_err(&rproc->dev, "failed to set pdds\n"); + return err; + } + } + + /* Update coprocessor state to OFF if available. */ + if (ddata->m4_state.map) { + err = regmap_update_bits(ddata->m4_state.map, + ddata->m4_state.reg, + ddata->m4_state.mask, + M4_STATE_OFF); + if (err) { + dev_err(&rproc->dev, "failed to set copro state\n"); + return err; + } + } + + return err; +} + +static int stm32_rproc_tee_elf_sanity_check(struct rproc *rproc, + const struct firmware *fw) +{ + struct stm32_rproc *ddata = rproc->priv; + unsigned int ret = 0; + + if (rproc->state == RPROC_DETACHED) + return 0; + + ret = tee_rproc_load_fw(ddata->trproc, fw); + if (!ret) + ddata->fw_loaded = true; + + return ret; +} + +static int stm32_rproc_tee_elf_load(struct rproc *rproc, + const struct firmware *fw) +{ + struct stm32_rproc *ddata = rproc->priv; + unsigned int ret; + + /* + * This function can be called by remote proc for recovery + * without the sanity check. In this case we need to load the firmware + * else nothing done here as the firmware has been preloaded for the + * sanity check to be able to parse it for the resource table + */ + if (ddata->fw_loaded) + return 0; + + ret = tee_rproc_load_fw(ddata->trproc, fw); + if (ret) + return ret; + ddata->fw_loaded = true; + + /* update the resource table parameters */ + if (rproc_tee_get_rsc_table(ddata->trproc)) { + /* no resource table: reset the related fields */ + rproc->cached_table = NULL; + rproc->table_ptr = NULL; + rproc->table_sz = 0; + } + + return 0; +} + +static struct resource_table * +stm32_rproc_tee_elf_find_loaded_rsc_table(struct rproc *rproc, + const struct firmware *fw) +{ + struct stm32_rproc *ddata = rproc->priv; + + return tee_rproc_get_loaded_rsc_table(ddata->trproc); +} + +static int stm32_rproc_tee_start(struct rproc *rproc) +{ + struct stm32_rproc *ddata = rproc->priv; + + return tee_rproc_start(ddata->trproc); +} + +static int stm32_rproc_tee_attach(struct rproc *rproc) +{ + /* Nothing to do, remote proc already started by the secured context */ + return 0; +} + +static int stm32_rproc_tee_stop(struct rproc *rproc) +{ + struct stm32_rproc *ddata = rproc->priv; + int err; + + stm32_rproc_request_shutdown(rproc); + + err = tee_rproc_stop(ddata->trproc); + if (err) + return err; + + ddata->fw_loaded = false; + + return stm32_rproc_release(rproc); +} + static int stm32_rproc_prepare(struct rproc *rproc) { struct device *dev = rproc->dev.parent; @@ -270,7 +413,14 @@ static int stm32_rproc_prepare(struct rproc *rproc)
static int stm32_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw) { - if (rproc_elf_load_rsc_table(rproc, fw)) + struct stm32_rproc *ddata = rproc->priv; + int ret; + + if (ddata->trproc) + ret = rproc_tee_get_rsc_table(ddata->trproc); + else + ret = rproc_elf_load_rsc_table(rproc, fw); + if (ret) dev_warn(&rproc->dev, "no resource table found for this firmware\n");
return 0; @@ -503,17 +653,9 @@ static int stm32_rproc_detach(struct rproc *rproc) static int stm32_rproc_stop(struct rproc *rproc) { struct stm32_rproc *ddata = rproc->priv; - int err, idx; + int err;
- /* request shutdown of the remote processor */ - if (rproc->state != RPROC_OFFLINE && rproc->state != RPROC_CRASHED) { - idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN); - if (idx >= 0 && ddata->mb[idx].chan) { - err = mbox_send_message(ddata->mb[idx].chan, "detach"); - if (err < 0) - dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n"); - } - } + stm32_rproc_request_shutdown(rproc);
err = stm32_rproc_set_hold_boot(rproc, true); if (err) @@ -525,29 +667,8 @@ static int stm32_rproc_stop(struct rproc *rproc) return err; }
- /* to allow platform Standby power mode, set remote proc Deep Sleep */ - if (ddata->pdds.map) { - err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg, - ddata->pdds.mask, 1); - if (err) { - dev_err(&rproc->dev, "failed to set pdds\n"); - return err; - } - } - - /* update coprocessor state to OFF if available */ - if (ddata->m4_state.map) { - err = regmap_update_bits(ddata->m4_state.map, - ddata->m4_state.reg, - ddata->m4_state.mask, - M4_STATE_OFF); - if (err) { - dev_err(&rproc->dev, "failed to set copro state\n"); - return err; - } - }
- return 0; + return stm32_rproc_release(rproc); }
static void stm32_rproc_kick(struct rproc *rproc, int vqid) @@ -659,8 +780,22 @@ static const struct rproc_ops st_rproc_ops = { .get_boot_addr = rproc_elf_get_boot_addr, };
+static const struct rproc_ops st_rproc_tee_ops = { + .prepare = stm32_rproc_prepare, + .start = stm32_rproc_tee_start, + .stop = stm32_rproc_tee_stop, + .attach = stm32_rproc_tee_attach, + .kick = stm32_rproc_kick, + .parse_fw = stm32_rproc_parse_fw, + .find_loaded_rsc_table = stm32_rproc_tee_elf_find_loaded_rsc_table, + .get_loaded_rsc_table = stm32_rproc_get_loaded_rsc_table, + .sanity_check = stm32_rproc_tee_elf_sanity_check, + .load = stm32_rproc_tee_elf_load, +}; + static const struct of_device_id stm32_rproc_match[] = { - { .compatible = "st,stm32mp1-m4" }, + {.compatible = "st,stm32mp1-m4",}, + {.compatible = "st,stm32mp1-m4-tee",}, {}, }; MODULE_DEVICE_TABLE(of, stm32_rproc_match); @@ -801,6 +936,7 @@ static int stm32_rproc_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct stm32_rproc *ddata; struct device_node *np = dev->of_node; + struct tee_rproc *trproc; struct rproc *rproc; unsigned int state; int ret; @@ -809,11 +945,29 @@ static int stm32_rproc_probe(struct platform_device *pdev) if (ret) return ret;
- rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata)); - if (!rproc) - return -ENOMEM; + if (of_device_is_compatible(np, "st,stm32mp1-m4-tee")) { + trproc = tee_rproc_register(dev, STM32_MP1_FW_ID); + if (IS_ERR_OR_NULL(trproc)) { + return PTR_ERR(trproc); + /* + * Delegate the firmware management to the secure context. + * The firmware loaded has to be signed. + */ + dev_info(dev, "Support of signed firmware only\n"); + } + } + rproc = rproc_alloc(dev, np->name, + trproc ? &st_rproc_tee_ops : &st_rproc_ops, + NULL, sizeof(*ddata)); + if (!rproc) { + ret = -ENOMEM; + goto free_tee; + }
ddata = rproc->priv; + ddata->trproc = trproc; + if (trproc) + ddata->trproc->rproc = rproc;
rproc_coredump_set_elf_info(rproc, ELFCLASS32, EM_NONE);
@@ -864,6 +1018,10 @@ static int stm32_rproc_probe(struct platform_device *pdev) device_init_wakeup(dev, false); } rproc_free(rproc); +free_tee: + if (trproc) + tee_rproc_unregister(trproc); + return ret; }
@@ -885,6 +1043,8 @@ static int stm32_rproc_remove(struct platform_device *pdev) device_init_wakeup(dev, false); } rproc_free(rproc); + if (ddata->trproc) + tee_rproc_unregister(ddata->trproc);
return 0; }