This is a note to let you know that I've just added the patch titled
net: qed: fix NVMe login fails over VFs
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-qed-fix-nvme-login-fails-over-vfs.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit fdc133113790657e92a2c45f3ba94f3cd2548b4e
Author: Alexander Lobakin <alobakin@xxxxxxxxxxx>
Date: Tue Jun 23 16:51:32 2020 +0300
net: qed: fix NVMe login fails over VFs
[ Upstream commit ccd7c7ce167a21dbf2b698ffcf00f11d96d44f9b ]
25ms sleep cycles in waiting for PF response are excessive and may lead
to different timeout failures.
Start to wait with short udelays, and in most cases polling will end
here. If the time was not sufficient, switch to msleeps.
usleep_range() may go far beyond 100us depending on platform and tick
configuration, hence atomic udelays for consistency.
Also add explicit DMA barriers since 'done' always comes from a shared
request-response DMA pool, and note that in the comment nearby.
Fixes: 1408cc1fa48c ("qed: Introduce VFs")
Signed-off-by: Alexander Lobakin <alobakin@xxxxxxxxxxx>
Signed-off-by: Igor Russkikh <irusskikh@xxxxxxxxxxx>
Signed-off-by: Michal Kalderon <michal.kalderon@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/qlogic/qed/qed_vf.c b/drivers/net/ethernet/qlogic/qed/qed_vf.c
index 856051f50eb75..adc2c8f3d48ef 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_vf.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_vf.c
@@ -81,12 +81,17 @@ static void qed_vf_pf_req_end(struct qed_hwfn *p_hwfn, int req_status)
mutex_unlock(&(p_hwfn->vf_iov_info->mutex));
}
+#define QED_VF_CHANNEL_USLEEP_ITERATIONS 90
+#define QED_VF_CHANNEL_USLEEP_DELAY 100
+#define QED_VF_CHANNEL_MSLEEP_ITERATIONS 10
+#define QED_VF_CHANNEL_MSLEEP_DELAY 25
+
static int qed_send_msg2pf(struct qed_hwfn *p_hwfn, u8 *done, u32 resp_size)
{
union vfpf_tlvs *p_req = p_hwfn->vf_iov_info->vf2pf_request;
struct ustorm_trigger_vf_zone trigger;
struct ustorm_vf_zone *zone_data;
- int rc = 0, time = 100;
+ int iter, rc = 0;
zone_data = (struct ustorm_vf_zone *)PXP_VF_BAR0_START_USDM_ZONE_B;
@@ -126,11 +131,19 @@ static int qed_send_msg2pf(struct qed_hwfn *p_hwfn, u8 *done, u32 resp_size)
REG_WR(p_hwfn, (uintptr_t)&zone_data->trigger, *((u32 *)&trigger));
/* When PF would be done with the response, it would write back to the
- * `done' address. Poll until then.
+ * `done' address from a coherent DMA zone. Poll until then.
*/
- while ((!*done) && time) {
- msleep(25);
- time--;
+
+ iter = QED_VF_CHANNEL_USLEEP_ITERATIONS;
+ while (!*done && iter--) {
+ udelay(QED_VF_CHANNEL_USLEEP_DELAY);
+ dma_rmb();
+ }
+
+ iter = QED_VF_CHANNEL_MSLEEP_ITERATIONS;
+ while (!*done && iter--) {
+ msleep(QED_VF_CHANNEL_MSLEEP_DELAY);
+ dma_rmb();
}
if (!*done) {
