Re: [PATCH 1/3] PCI: rcar-gen4: Configure AXIINTC if iMSI-RX not used

From: Marek Vasut

Date: Wed Jun 17 2026 - 22:54:13 EST


On 6/17/26 10:26 AM, Geert Uytterhoeven wrote:

Hello Geert,

+static void rcar_gen4_pcie_host_msi_init(struct dw_pcie_rp *pp)
+{
+ struct dw_pcie *dw = to_dw_pcie_from_pp(pp);
+ struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw);
+ u32 val;
+
+ /* Make sure MSICAP0 MSIE is configured. */
+ val = dw_pcie_readl_dbi(dw, MSICAP0);
+ if (pci_msi_enabled())
+ val |= MSICAP0_MSIE;
+ else
+ val &= ~MSICAP0_MSIE;
+ dw_pcie_writel_dbi(dw, MSICAP0, val);
+
+ if (!pci_msi_enabled() || pp->use_imsi_rx) {
+ /* Clear AXIINTC mapping. */
+ writel(0, rcar->base + AXIINTCADDR);
+ writel(0, rcar->base + AXIINTCCONT);
+ } else {
+ /* Point AXIINTC to GIC ITS and enable. */
+ writel(AXIINTCADDR_VAL, rcar->base + AXIINTCADDR);
+ writel(INTC_EN | INTC_MASK, rcar->base + AXIINTCCONT);
+ }
+
+ /* Configure MSI interrupt signal */
+ val = readl(rcar->base + PCIEINTSTS0EN);
+ if (pci_msi_enabled())
+ val |= MSI_CTRL_INT;
+ else
+ val &= ~MSI_CTRL_INT;
+ writel(val, rcar->base + PCIEINTSTS0EN);
+}
+
static int rcar_gen4_pcie_enable_device(struct pci_host_bridge *bridge,

FTR, this has a contextual dependency on "[PATCH v2] PCI: rcar-gen4:
Limit Max_Read_Request_Size and Max_Payload_Size to 256 Bytes"
(https://lore.kernel.org/all/20260519195219.189323-1-marek.vasut+renesas@xxxxxxxxxxx).
It is not an explicit dependency, I only had these patches in my tree and clearly that was an interaction. I'll rebase this dependency out for V2.

Thanks!

--
Best regards,
Marek Vasut