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authorShawn Guo <shengchao.guo@oss.qualcomm.com>2026-09-22 10:06:23 +0800
committerGeorgi Djakov <djakov@kernel.org>2026-09-22 16:59:22 +0300
commite0667aa9c6f997e827ba9444d19550dea95d2169 (patch)
treedc8d779f6ace2b40a9228418d1098956d15e6801 /tools/perf/scripts/python/stackcollapse.py
parent11a44c6087c64087c99d5d90313473eceb51296c (diff)
downloadlinux-next-e0667aa9c6f997e827ba9444d19550dea95d2169.tar.gz
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interconnect: qcom: Skip get_bw on QoS programming providers
Programming the static QoS configuration in qcom_icc_rpmh_probe() touches NoC registers directly, and nothing in that path clocks or powers the NoC first. It has been working only because the interconnect core used to vote every node to INT_MAX while adding it, and that vote stays in hardware until sync_state. Reading the boot-time AMC votes back from RPMh removed that implicit guarantee: a NoC whose BCMs come out of the bootloader unvoted is now left unclocked, and the first QoS register access aborts. On Qualcomm Nord SoC, the MMSS NoC dies while programming qnm_camnoc_hf, taking the board down before rootfs: Internal error: synchronous external abort: 0000000096001610 regmap_mmio_read32le+0xc/0xa4 regmap_update_bits_base+0x64/0x98 qcom_icc_rpmh_probe+0x44c/0x540 Only install the get_bw() callback for providers that do not program QoS, i.e. those without a regmap config. Providers that do program QoS keep the previous INT_MAX initial votes, so their register accesses stay safe, and the rest keep the benefit of honouring the boot-time votes. Reported-by: Bartosz Golaszewski <brgl@kernel.org> Fixes: 11a44c6087c6 ("interconnect: qcom: implement get_bw with rpmh_read") Assisted-by: LLM Signed-off-by: Shawn Guo <shengchao.guo@oss.qualcomm.com> Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com> Tested-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com> Link: https://patch.msgid.link/20260922020623.398913-1-shengchao.guo@oss.qualcomm.com Signed-off-by: Georgi Djakov <djakov@kernel.org>
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