6.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org
[ Upstream commit b9cbc06049cb6b7a322d708c2098195fb9fdcc4c ]
Currently, as part of the qcom_pcie_perst_deassert() function, instead of writing the updated value to clear PARF_MSTR_AXI_CLK_EN, the variable "val" is re-read.
This must be fixed to ensure that the master clock supplied to the MHI bus is correctly gated during L1.1/L1.2 to save power.
Thus, replace the line that re-reads "val" with a line that writes the updated value to the register to clear PARF_MSTR_AXI_CLK_EN.
[kwilczynski: commit log] Fixes: c457ac029e44 ("PCI: qcom-ep: Gate Master AXI clock to MHI bus during L1SS") Link: https://lore.kernel.org/linux-pci/20230627141036.11600-1-manivannan.sadhasiv... Reported-by: Krzysztof Wilczyński kwilczynski@kernel.org Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org Signed-off-by: Krzysztof Wilczyński kwilczynski@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/controller/dwc/pcie-qcom-ep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c index 19b32839ea261..043b356d7d72d 100644 --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c @@ -415,7 +415,7 @@ static int qcom_pcie_perst_deassert(struct dw_pcie *pci) /* Gate Master AXI clock to MHI bus during L1SS */ val = readl_relaxed(pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL); val &= ~PARF_MSTR_AXI_CLK_EN; - val = readl_relaxed(pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL); + writel_relaxed(val, pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL);
dw_pcie_ep_init_notify(&pcie_ep->pci.ep);