[PATCH v4 9/9] PCI: dwc: Do not write to MSI control registers if the platform doesn't use it
From: Kishon Vijay Abraham I <hidden>
Date: 2019-02-21 10:19:13
Also in:
linux-pci, lkml
Subsystem:
pci driver for synopsys designware, pci native host bridge and endpoint drivers, pci subsystem, the rest · Maintainers:
Jingoo Han, Manivannan Sadhasivam, Lorenzo Pieralisi, Krzysztof Wilczyński, Bjorn Helgaas, Linus Torvalds
Platforms which populate msi_host_init, has it's own MSI controller logic. Writing to MSI control registers on platforms which doesn't use Designware's MSI controller logic might have side effects. To be safe, do not write to MSI control registers if the platform uses it's own MSI controller logic instead of Designware's MSI controller logic. Signed-off-by: Kishon Vijay Abraham I <redacted> --- .../pci/controller/dwc/pcie-designware-host.c | 24 ++++++++++--------- 1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 781735f06dea..2bc2fd582124 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c@@ -641,17 +641,19 @@ void dw_pcie_setup_rc(struct pcie_port *pp) dw_pcie_setup(pci); - num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL; - - /* Initialize IRQ Status array */ - for (ctrl = 0; ctrl < num_ctrls; ctrl++) { - dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_MASK + - (ctrl * MSI_REG_CTRL_BLOCK_SIZE), - 4, ~0); - dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_ENABLE + - (ctrl * MSI_REG_CTRL_BLOCK_SIZE), - 4, ~0); - pp->irq_status[ctrl] = 0; + if (!pp->ops->msi_host_init) { + num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL; + + /* Initialize IRQ Status array */ + for (ctrl = 0; ctrl < num_ctrls; ctrl++) { + dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_MASK + + (ctrl * MSI_REG_CTRL_BLOCK_SIZE), + 4, ~0); + dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_ENABLE + + (ctrl * MSI_REG_CTRL_BLOCK_SIZE), + 4, ~0); + pp->irq_status[ctrl] = 0; + } } /* Setup RC BARs */
--
2.17.1
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