On Fri, Mar 08, 2024 at 03:47:08PM +0100, Arnaud Pouliquen wrote:
> The new TEE remoteproc device is used to manage remote firmware in a
> secure, trusted context. The 'st,stm32mp1-m4-tee' compatibility is
> introduced to delegate the loading of the firmware to the trusted
> execution context. In such cases, the firmware should be signed and
> adhere to the image format defined by the TEE.
>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
> ---
> Updates from V3:
> - remove support of the attach use case. Will be addressed in a separate
> thread,
> - add st_rproc_tee_ops::parse_fw ops,
> - inverse call of devm_rproc_alloc()and tee_rproc_register() to manage cross
> reference between the rproc struct and the tee_rproc struct in tee_rproc.c.
> ---
> drivers/remoteproc/stm32_rproc.c | 60 +++++++++++++++++++++++++++++---
> 1 file changed, 56 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
> index 8cd838df4e92..13df33c78aa2 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 +50,9 @@
> #define M4_STATE_STANDBY 4
> #define M4_STATE_CRASH 5
>
> +/* Remote processor unique identifier aligned with the Trusted Execution Environment definitions */
Why is this the case? At least from the kernel side it is possible to call
tee_rproc_register() with any kind of value, why is there a need to be any
kind of alignment with the TEE?
> +#define STM32_MP1_M4_PROC_ID 0
> +
> struct stm32_syscon {
> struct regmap *map;
> u32 reg;
> @@ -257,6 +261,19 @@ static int stm32_rproc_release(struct rproc *rproc)
> return 0;
> }
>
> +static int stm32_rproc_tee_stop(struct rproc *rproc)
> +{
> + int err;
> +
> + stm32_rproc_request_shutdown(rproc);
> +
> + err = tee_rproc_stop(rproc);
> + if (err)
> + return err;
> +
> + return stm32_rproc_release(rproc);
> +}
> +
> static int stm32_rproc_prepare(struct rproc *rproc)
> {
> struct device *dev = rproc->dev.parent;
> @@ -693,8 +710,19 @@ 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 = tee_rproc_start,
> + .stop = stm32_rproc_tee_stop,
> + .kick = stm32_rproc_kick,
> + .load = tee_rproc_load_fw,
> + .parse_fw = tee_rproc_parse_fw,
> + .find_loaded_rsc_table = tee_rproc_find_loaded_rsc_table,
> +};
> +
> 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);
> @@ -853,6 +881,7 @@ 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 = NULL;
> struct rproc *rproc;
> unsigned int state;
> int ret;
> @@ -861,9 +890,26 @@ static int stm32_rproc_probe(struct platform_device *pdev)
> if (ret)
> return ret;
>
> - rproc = devm_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")) {
> + /*
> + * Delegate the firmware management to the secure context.
> + * The firmware loaded has to be signed.
> + */
> + rproc = devm_rproc_alloc(dev, np->name, &st_rproc_tee_ops, NULL, sizeof(*ddata));
> + if (!rproc)
> + return -ENOMEM;
> +
> + trproc = tee_rproc_register(dev, rproc, STM32_MP1_M4_PROC_ID);
> + if (IS_ERR(trproc)) {
> + dev_err_probe(dev, PTR_ERR(trproc),
> + "signed firmware not supported by TEE\n");
> + return PTR_ERR(trproc);
> + }
> + } else {
> + rproc = devm_rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
> + if (!rproc)
> + return -ENOMEM;
> + }
>
> ddata = rproc->priv;
>
> @@ -915,6 +961,9 @@ static int stm32_rproc_probe(struct platform_device *pdev)
> dev_pm_clear_wake_irq(dev);
> device_init_wakeup(dev, false);
> }
> + if (trproc)
if (rproc->tee_interface)
I am done reviewing this set.
Thanks,
Mathieu
> + tee_rproc_unregister(trproc);
> +
> return ret;
> }
>
> @@ -935,6 +984,9 @@ static void stm32_rproc_remove(struct platform_device *pdev)
> dev_pm_clear_wake_irq(dev);
> device_init_wakeup(dev, false);
> }
> + if (rproc->tee_interface)
> + tee_rproc_unregister(rproc->tee_interface);
> +
> }
>
> static int stm32_rproc_suspend(struct device *dev)
> --
> 2.25.1
>
