mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-04 16:15:11 +00:00
Code Issues Releases Wiki Activity

net: ipa: support retries on generic GSI commands

Browse source 
When stopping an AP RX channel, there can be a transient period
while the channel enters STOP_IN_PROC state before reaching the
final STOPPED state.  In that case we make another attempt to stop
the channel.

Similarly, when stopping a modem channel (using a GSI generic
command issued from the AP), it's possible that multiple attempts
will be required before the channel reaches STOPPED state.

Add a field to the GSI structure to record an errno representing the
result code provided when a generic command completes.  If the
result learned in gsi_isr_gp_int1() is RETRY, record -EAGAIN in the
result code, otherwise record 0 for success, or -EIO for any other
result.

If we time out nf gsi_generic_command() waiting for the command to
complete, return -ETIMEDOUT (as before).  Otherwise return the
result stashed by gsi_isr_gp_int1().

Add a loop in gsi_modem_channel_halt() to reissue the HALT command
if the result code indicates -EAGAIN.  Limit this to 10 retries
(after the initial attempt).

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Alex Elder 2020-11-19 16:49:27 -06:00 committed by Jakub Kicinski
parent f849afcc8c
commit 1136145660
2 changed files with 20 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

21
drivers/net/ipa/gsi.c
View file

@ -92,6 +92,7 @@
#define GSI_CMD_TIMEOUT 5 /* seconds */
#define GSI_CHANNEL_STOP_RX_RETRIES 10
#define GSI_CHANNEL_MODEM_HALT_RETRIES 10
#define GSI_MHI_EVENT_ID_START 10 /* 1st reserved event id */
#define GSI_MHI_EVENT_ID_END 16 /* Last reserved event id */
@ -1107,10 +1108,16 @@ static void gsi_isr_gp_int1(struct gsi *gsi)
switch (result) {
case GENERIC_EE_SUCCESS:
case GENERIC_EE_CHANNEL_NOT_RUNNING:
gsi->result = 0;
break;
case GENERIC_EE_RETRY:
gsi->result = -EAGAIN;
break;
default:
dev_err(gsi->dev, "global INT1 generic result %u\n", result);
gsi->result = -EIO;
break;
}
@ -1624,7 +1631,7 @@ static int gsi_generic_command(struct gsi *gsi, u32 channel_id,
iowrite32(BIT(ERROR_INT), gsi->virt + GSI_CNTXT_GLOB_IRQ_EN_OFFSET);
if (success)
return 0;
return gsi->result;
dev_err(gsi->dev, "GSI generic command %u to channel %u timed out\n",
opcode, channel_id);
@ -1640,7 +1647,17 @@ static int gsi_modem_channel_alloc(struct gsi *gsi, u32 channel_id)
static void gsi_modem_channel_halt(struct gsi *gsi, u32 channel_id)
{
(void)gsi_generic_command(gsi, channel_id, GSI_GENERIC_HALT_CHANNEL);
u32 retries = GSI_CHANNEL_MODEM_HALT_RETRIES;
int ret;
do
ret = gsi_generic_command(gsi, channel_id,
GSI_GENERIC_HALT_CHANNEL);
while (ret == -EAGAIN && retries--);
if (ret)
dev_err(gsi->dev, "error %d halting modem channel %u\n",
ret, channel_id);
}
/* Setup function for channels */

1
drivers/net/ipa/gsi.h
View file

@ -161,6 +161,7 @@ struct gsi {
u32 type_enabled_bitmap; /* GSI IRQ types enabled */
u32 ieob_enabled_bitmap; /* IEOB IRQ enabled (event rings) */
struct completion completion; /* for global EE commands */
int result; /* Negative errno (generic commands) */
struct mutex mutex; /* protects commands, programming */
};