This is a note to let you know that I've just added the patch titled
drm/amdgpu: fix the hang caused by PCIe link width switch
to the 5.12-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:
drm-amdgpu-fix-the-hang-caused-by-pcie-link-width-switch.patch
and it can be found in the queue-5.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From adcf949e664a8b04df2fb8aa916892e58561653c Mon Sep 17 00:00:00 2001
From: Evan Quan <evan.quan@xxxxxxx>
Date: Tue, 25 May 2021 14:36:29 +0800
Subject: drm/amdgpu: fix the hang caused by PCIe link width switch
From: Evan Quan <evan.quan@xxxxxxx>
commit adcf949e664a8b04df2fb8aa916892e58561653c upstream.
SMU had set all the necessary fields for a link width switch
but the width switch wasn't occurring because the link was idle
in the L1 state. Setting LC_L1_RECONFIG_EN=0x1 will allow width
switches to also be initiated while in L1 instead of waiting until
the link is back in L0.
Signed-off-by: Evan Quan <evan.quan@xxxxxxx>
Reviewed-by: Lijo Lazar <lijo.lazar@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_nbio.h | 1 +
drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c | 13 +++++++++++++
drivers/gpu/drm/amd/amdgpu/nv.c | 3 +++
3 files changed, 17 insertions(+)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_nbio.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_nbio.h
@@ -90,6 +90,7 @@ struct amdgpu_nbio_funcs {
bool enable);
void (*program_aspm)(struct amdgpu_device *adev);
void (*apply_lc_spc_mode_wa)(struct amdgpu_device *adev);
+ void (*apply_l1_link_width_reconfig_wa)(struct amdgpu_device *adev);
};
struct amdgpu_nbio {
--- a/drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c
+++ b/drivers/gpu/drm/amd/amdgpu/nbio_v2_3.c
@@ -490,6 +490,18 @@ static void nbio_v2_3_apply_lc_spc_mode_
}
}
+static void nbio_v2_3_apply_l1_link_width_reconfig_wa(struct amdgpu_device *adev)
+{
+ uint32_t reg_data = 0;
+
+ if (adev->asic_type != CHIP_NAVI10)
+ return;
+
+ reg_data = RREG32_PCIE(smnPCIE_LC_LINK_WIDTH_CNTL);
+ reg_data |= PCIE_LC_LINK_WIDTH_CNTL__LC_L1_RECONFIG_EN_MASK;
+ WREG32_PCIE(smnPCIE_LC_LINK_WIDTH_CNTL, reg_data);
+}
+
const struct amdgpu_nbio_funcs nbio_v2_3_funcs = {
.get_hdp_flush_req_offset = nbio_v2_3_get_hdp_flush_req_offset,
.get_hdp_flush_done_offset = nbio_v2_3_get_hdp_flush_done_offset,
@@ -512,4 +524,5 @@ const struct amdgpu_nbio_funcs nbio_v2_3
.enable_aspm = nbio_v2_3_enable_aspm,
.program_aspm = nbio_v2_3_program_aspm,
.apply_lc_spc_mode_wa = nbio_v2_3_apply_lc_spc_mode_wa,
+ .apply_l1_link_width_reconfig_wa = nbio_v2_3_apply_l1_link_width_reconfig_wa,
};
--- a/drivers/gpu/drm/amd/amdgpu/nv.c
+++ b/drivers/gpu/drm/amd/amdgpu/nv.c
@@ -1076,6 +1076,9 @@ static int nv_common_hw_init(void *handl
if (adev->nbio.funcs->apply_lc_spc_mode_wa)
adev->nbio.funcs->apply_lc_spc_mode_wa(adev);
+ if (adev->nbio.funcs->apply_l1_link_width_reconfig_wa)
+ adev->nbio.funcs->apply_l1_link_width_reconfig_wa(adev);
+
/* enable pcie gen2/3 link */
nv_pcie_gen3_enable(adev);
/* enable aspm */
Patches currently in stable-queue which might be from evan.quan@xxxxxxx are
queue-5.12/drm-amdgpu-fix-nak-g-generation-during-pci-e-link-width-switch.patch
queue-5.12/drm-amd-display-fix-incorrrect-valid-irq-check.patch
queue-5.12/drm-amdgpu-fix-the-hang-caused-by-pcie-link-width-switch.patch
