[PATCH v3] soc: qcom: ubwc: Fix link error when QCOM_SMEM=n
From: Daniel Baluta
Date: Wed Aug 12 2026 - 09:07:48 EST
DRM_MSM unconditionally selects QCOM_UBWC_CONFIG, which calls SMEM APIs,
causing a link error on non-Qcom platforms (e.g. SOC_IMX5):
arm-linux-gnueabihf-ld: ubwc_config.c:(.text+0x2c): undefined
reference to 'qcom_smem_is_available'
arm-linux-gnueabihf-ld: ubwc_config.c:(.text+0x4c): undefined
reference to 'qcom_smem_dram_get_hbb'
Make QCOM_UBWC_CONFIG depend on QCOM_SMEM to make the requirement
explicit, and guard the select in DRM_MSM with ARCH_QCOM && QCOM_SMEM so
it is only selected when its dependency is met.
Fixes: 1b445022d1d0 ("soc: qcom: ubwc: Get HBB from SMEM")
Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
---
Changes since v2:
- guard QCOM_UBWC_CONFIG both with ARCH_QCOM and QCOM_SMEM otherwise
we could force QCOM_SMEM=n and still have QCOM_UBWC_CONFIG=m as reported
by Nathan Chancellor
- Link to v2: https://lore.kernel.org/imx/20260811223622.GA934543@ax162/T/#t
Changes since v1:
- (addressed feedback from Dmitry) replace adding static inline stubs with preparing a better config
dependecies so that we use the qcom_smem symbols only on QCOM platforms.
- Link to v1: https://lore.kernel.org/imx/sy2ulk536ryakhy6fdnqr4asvzvufqk3dlo2awdrfomulyf4n4@qtp4qoazqmhj/T/#t
drivers/gpu/drm/msm/Kconfig | 2 +-
drivers/soc/qcom/Kconfig | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/Kconfig b/drivers/gpu/drm/msm/Kconfig
index 09469d56513b0..1670dbc9464c6 100644
--- a/drivers/gpu/drm/msm/Kconfig
+++ b/drivers/gpu/drm/msm/Kconfig
@@ -22,7 +22,7 @@ config DRM_MSM
select TMPFS
select QCOM_SCM
select QCOM_PAS
- select QCOM_UBWC_CONFIG
+ select QCOM_UBWC_CONFIG if ARCH_QCOM && QCOM_SMEM
select WANT_DEV_COREDUMP
select SND_SOC_HDMI_CODEC if SND_SOC
select SYNC_FILE
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index fd4d4ecd2df0f..e0629e9328c87 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -321,6 +321,7 @@ config QCOM_QMI_HELPERS
config QCOM_UBWC_CONFIG
tristate
+ depends on QCOM_SMEM
help
Most Qualcomm SoCs feature a number of Universal Bandwidth Compression
(UBWC) engines across various IP blocks, which need to be initialized
--
2.45.2