Re: [PATCH v9 7/7] remoteproc: stm32: Add support of an OP-TEE TA to load the firmware

Arnaud POULIQUEN
2024-09-16T14:11:58Z

Hello Mathieu,

On 9/13/24 18:03, Mathieu Poirier wrote:
> On Fri, Aug 30, 2024 at 11:51:47AM +0200, Arnaud Pouliquen wrote:
>> The new TEE remoteproc driver 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@foss.st.com>
>> ---
>> drivers/remoteproc/stm32_rproc.c | 63 ++++++++++++++++++++++++++++++--
>> 1 file changed, 60 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
>> index 79c638936163..400a7a93b1c9 100644
>> --- a/drivers/remoteproc/stm32_rproc.c
>> +++ b/drivers/remoteproc/stm32_rproc.c
>> @@ -18,6 +18,7 @@
>> #include <linux/pm_wakeirq.h>
>> #include <linux/regmap.h>
>> #include <linux/remoteproc.h>
>> +#include <linux/remoteproc_tee.h>
>> #include <linux/reset.h>
>> #include <linux/slab.h>
>> #include <linux/workqueue.h>
>> @@ -257,6 +258,19 @@ 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 +707,20 @@ 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-tee" },
>> {},
>> };
>> MODULE_DEVICE_TABLE(of, stm32_rproc_match);
>> @@ -853,17 +879,42 @@ 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;
>> + u32 proc_id;
>> int ret;
>>
>> ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
>> 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.
>> + */
>> + ret = of_property_read_u32(np, "st,proc-id", &proc_id);
>> + if (ret) {
>> + dev_err(dev, "failed to read st,rproc-id property\n");
>> + return ret;
>> + }
>> +
>> + rproc = devm_rproc_alloc(dev, np->name, &st_rproc_tee_ops, NULL, sizeof(*ddata));
>> + if (!rproc)
>> + return -ENOMEM;
>> +
>> + trproc = tee_rproc_register(dev, rproc, 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 +966,9 @@ 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 for the review, I will sent a V10 ASAP to fix this set.
Extra information: the OP-TEE that introduces the new
PTA_REMOTEPROC_RELEASE command has been merged.

Regards,
Arnaud

>
>> + tee_rproc_unregister(trproc);
>> +
>> return ret;
>> }
>>
>> @@ -935,6 +989,9 @@ 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
>>