[PATCH 5.10 073/154] net: ipa: disable HOLB drop when updating timer

From: Greg Kroah-Hartman
Date: Wed Nov 24 2021 - 08:38:50 EST


From: Alex Elder <elder@xxxxxxxxxx>

[ Upstream commit 816316cacad2b5abd5b41423cf04e4845239abd4 ]

The head-of-line blocking timer should only be modified when
head-of-line drop is disabled.

One of the steps in recovering from a modem crash is to enable
dropping of packets with timeout of 0 (immediate). We don't know
how the modem configured its endpoints, so before we program the
timer, we need to ensure HOL_BLOCK is disabled.

Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints")
Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ipa/ipa_endpoint.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -703,6 +703,7 @@ static void ipa_endpoint_init_hol_block_
u32 offset;
u32 val;

+ /* This should only be changed when HOL_BLOCK_EN is disabled */
offset = IPA_REG_ENDP_INIT_HOL_BLOCK_TIMER_N_OFFSET(endpoint_id);
val = ipa_reg_init_hol_block_timer_val(ipa, microseconds);
iowrite32(val, ipa->reg_virt + offset);
@@ -730,6 +731,7 @@ void ipa_endpoint_modem_hol_block_clear_
if (endpoint->toward_ipa || endpoint->ee_id != GSI_EE_MODEM)
continue;

+ ipa_endpoint_init_hol_block_enable(endpoint, false);
ipa_endpoint_init_hol_block_timer(endpoint, 0);
ipa_endpoint_init_hol_block_enable(endpoint, true);
}