Hi Abdellatif,
On Fri, Jan 26, 2024 at 7:20 PM Abdellatif El Khlifi abdellatif.elkhlifi@arm.com wrote:
Hi Weizhao,
On Thu, Jan 25, 2024 at 02:05:00PM +0000, Weizhao Ouyang wrote:
According to PSCI specification DEN0022F, PSCI_FEATURES is used to check whether the SMCCC is implemented by discovering SMCCC_VERSION.
Signed-off-by: Weizhao Ouyang o451686892@gmail.com
drivers/firmware/psci.c | 2 +- include/linux/arm-smccc.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index c6b9efab41..894be8128d 100644 --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -135,7 +135,7 @@ static int bind_smccc_features(struct udevice *dev, int psci_method) PSCI_VERSION_MAJOR(psci_0_2_get_version()) == 0) return 0;
if (request_psci_features(ARM_SMCCC_ARCH_FEATURES) ==
if (request_psci_features(ARM_SMCCC_VERSION) == PSCI_RET_NOT_SUPPORTED) return 0;I suggest we add checks on the SMCCC version like this:
if SMCCC_VERSION >= 1.1 assume SMCCC_ARCH_FEATURES is supported discover arch features and bind drivers/devices else error
Okay, I will add it.
BR, Weizhao
For more details [1][2].
[1]: SMC Calling Convention 1.5 (https://developer.arm.com/documentation/den0028/latest/)
SMCCC_ARCH_FEATURES MANDATORY from SMCCC v1.1
The implementation of this function can be detected by checking the SMCCC version. This function is mandatory if SMCCC_VERSION indicates that version 1.1 or later is implemented.
[2]: Linux checks SMCCC v1.1: https://elixir.bootlin.com/linux/latest/source/drivers/firmware/psci/psci.c#...
Cheers, Abdellatif