diff options
Diffstat (limited to 'drivers/rpmsg/imx_rpmsg.c')
| -rw-r--r-- | drivers/rpmsg/imx_rpmsg.c | 31 |
1 files changed, 28 insertions, 3 deletions
diff --git a/drivers/rpmsg/imx_rpmsg.c b/drivers/rpmsg/imx_rpmsg.c index e8878967b6cc..9dfb49881a31 100644 --- a/drivers/rpmsg/imx_rpmsg.c +++ b/drivers/rpmsg/imx_rpmsg.c @@ -105,6 +105,14 @@ struct imx_rpmsg_vproc { #define to_imx_virdev(vd) container_of(vd, struct imx_virdev, vdev) +/* Flag 0 of ASR, 1 indicated that remote processor is ready */ +#define REMOTE_IS_READY BIT(0) +/* + * The time consumption by remote ready is less than 1ms in the + * evaluation. Set the max wait timeout as 50ms here. + */ +#define REMOTE_READY_WAIT_MAX_RETRIES 500 + struct imx_rpmsg_vq_info { __u16 num; /* number of entries in the virtio_ring */ __u16 vq_id; /* a globaly unique index of this virtqueue */ @@ -149,10 +157,12 @@ static bool imx_rpmsg_notify(struct virtqueue *vq) * is running normally or in the suspend mode. Only use * the timeout mechanism by the first notify when the vdev is * registered. + * ~14ms is required by M4 ready to process the MU message from + * cold boot. Set the wait time 20ms here. */ if (unlikely(rpvq->rpdev->first_notify > 0)) { rpvq->rpdev->first_notify--; - MU_SendMessageTimeout(rpvq->rpdev->mu_base, 1, mu_rpmsg, 200); + MU_SendMessageTimeout(rpvq->rpdev->mu_base, 1, mu_rpmsg, 2000); } else { MU_SendMessage(rpvq->rpdev->mu_base, 1, mu_rpmsg); } @@ -503,6 +513,7 @@ static int imx_rpmsg_mu_init(struct imx_rpmsg_vproc *rpdev) void imx_rpmsg_restore(struct imx_rpmsg_vproc *rpdev) { int i; + u32 flags; int vdev_nums = rpdev->vdev_nums; for (i = 0; i < vdev_nums; i++) { @@ -510,8 +521,22 @@ void imx_rpmsg_restore(struct imx_rpmsg_vproc *rpdev) kfree(rpdev->ivdev[i]); } - /* Wait a while for remote bootup */ - usleep_range(10000, 20000); + /* Make a double check that remote processor is ready or not */ + for (i = 0; i < REMOTE_READY_WAIT_MAX_RETRIES; i++) { + flags = MU_ReadStatus(rpdev->mu_base); + if (flags & REMOTE_IS_READY) + break; + usleep_range(100, 200); + } + if (unlikely((flags & REMOTE_IS_READY) == 0)) { + pr_err("Wait for remote ready timeout, assume it's dead.\n"); + /* + * In order to make the codes to be robust and back compatible. + * When wait remote ready timeout, use the MU_SendMessageTimeout + * to send the first kick-off message when register the vdev. + */ + rpdev->first_notify = rpdev->vdev_nums; + } /* Allocate and setup ivdev again to register virtio devices */ if (set_vring_phy_buf(rpdev->pdev, rpdev, rpdev->vdev_nums)) |