Hi Rajat,
On 12/31/21 16:49, Khandelwal, Rajat wrote:
> Adding ++Heikki
>
> Thanks
> Rajat
If you want me to apply this, please send this as a proper patch, not as an inline
forward to me, with the platform-driver-x86@xxxxxxxxxxxxxxx list in the Cc.
Regards,
Hans
> -----Original Message-----
> From: Khandelwal, Rajat <rajat.khandelwal@xxxxxxxxx>
> Sent: Thursday, December 30, 2021 1:54 PM
> To: mika.westerberg@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx; platform-driver-x86@xxxxxxxxxxxxxxx; Khandelwal, Rajat <rajat.khandelwal@xxxxxxxxx>; Westerberg, Mika <mika.westerberg@xxxxxxxxx>
> Subject: [PATCH] platform/x86: intel_scu_ipc: Keep polling IPC status if it reads IPC_STATUS_ERR
>
> The current implementation returns -EIO if and when IPC_STATUS_ERR is returned and returns -ETIMEDOUT even if the status is busy.
> This patch polls the IPC status even if IPC_STATUS_ERR is returned until timeout expires and returns -EBUSY if the status shows busy.
> Observed in multiple scenarios, trying to fetch the status of IPC after it shows ERR sometimes eradicates the ERR status.
>
> Signed-off-by: Rajat-Khandelwal <rajat.khandelwal@xxxxxxxxx>
> ---
> drivers/platform/x86/intel_scu_ipc.c | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c
> index 7cc9089d1e14..1f90acaa7212 100644
> --- a/drivers/platform/x86/intel_scu_ipc.c
> +++ b/drivers/platform/x86/intel_scu_ipc.c
> @@ -233,17 +233,23 @@ static inline u32 ipc_data_readl(struct intel_scu_ipc_dev *scu, u32 offset) static inline int busy_loop(struct intel_scu_ipc_dev *scu) {
> unsigned long end = jiffies + IPC_TIMEOUT;
> + u32 status;
>
> do {
> - u32 status;
> -
> status = ipc_read_status(scu);
> - if (!(status & IPC_STATUS_BUSY))
> - return (status & IPC_STATUS_ERR) ? -EIO : 0;
> + if (!(status & IPC_STATUS_BUSY)) {
> + if (!(status & IPC_STATUS_ERR))
> + return 0;
> + }
>
> usleep_range(50, 100);
> } while (time_before(jiffies, end));
>
> + if (status & IPC_STATUS_BUSY)
> + return -EBUSY;
> + if (status & IPC_STATUS_ERR)
> + return -EIO;
> +
> return -ETIMEDOUT;
> }
>
> --
> 2.17.1
>
