[PATCH 5.15 115/279] net: ipa: disable HOLB drop when updating timer

Greg Kroah-Hartman
2021-11-24T13:52:08Z

From: Alex Elder <elder@linaro.org>

[ 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@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ipa/ipa_endpoint.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index 006da4642a0ba..ef790fd0ab56a 100644
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -853,6 +853,7 @@ static void ipa_endpoint_init_hol_block_timer(struct ipa_endpoint *endpoint,
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 = hol_block_timer_val(ipa, microseconds);
iowrite32(val, ipa->reg_virt + offset);
@@ -883,6 +884,7 @@ void ipa_endpoint_modem_hol_block_clear_all(struct ipa *ipa)
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);
}
--
2.33.0