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

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

[Marek Vasut]

In case MSI are enabled, but DWC built-in iMSI-RX is not in use, the
MSI are handled via GIC ITS. Configure all controller MSI registers
fully.

Set or clear MSI capability register MSICAP0 MSI enable MSIE bit and
PCIe Interrupt Status 0 Enable register PCIEINTSTS0EN MSI interrupt
enable MSI_CTRL_INT bit according to MSI enable state, set both bits
if MSI are enabled, clear both bits if MSI are disabled.

If MSI are disabled, or MSI are enabled and iMSI-RX is used, then
deconfigure AXIINTCADDR and AXIINTCCONT to 0, which disables any
pass through of MSI TLPs onto the AXI bus and then further into
GIC ITS translation registers.

If MSI are enabled and iMSI-RX is not used, the configure AXIINTCADDR
with target address of GIC ITS translation registers, and configure
AXIINTCCONT to enable MSI TLP pass through onto AXI bus and into the
GIC ITS. This specific configuration allows handling of MSI via the
GIC ITS instead of integrated iMSI-RX.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
---
NOTE: This would not be possible without prior work from Shimoda-san
---
Cc: "Krzysztof Wilczyński" <kwilczynski@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-renesas-soc@vger.kernel.org
---
 drivers/pci/controller/dwc/pcie-rcar-gen4.c | 53 +++++++++++++++++++--
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index 485cfa8bd9692..ba6e3bedd6d0a 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -31,6 +31,10 @@
 #define DEVICE_TYPE_RC		BIT(4)
 #define BIFUR_MOD_SET_ON	BIT(0)
 
+/* MSI Capability */
+#define MSICAP0			0x0050
+#define MSICAP0_MSIE		BIT(16)
+
 /* PCIe Interrupt Status 0 */
 #define PCIEINTSTS0		0x0084
 
@@ -55,6 +59,16 @@
 #define APP_HOLD_PHY_RST	BIT(16)
 #define APP_LTSSM_ENABLE	BIT(0)
 
+/* INTC address */
+#define AXIINTCADDR		0x0a00
+/* GITS GIC ITS translation register */
+#define AXIINTCADDR_VAL		0xf1050000
+
+/* INTC control & mask */
+#define AXIINTCCONT		0x0a04
+#define INTC_EN			BIT(31)
+#define INTC_MASK		GENMASK(11, 2)
+
 /* PCIe Power Management Control */
 #define PCIEPWRMNGCTRL		0x0070
 #define APP_CLK_REQ_N		BIT(11)
@@ -305,6 +319,39 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
 	return rcar;
 }
 
+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,
 					struct pci_dev *dev)
 {
@@ -359,7 +406,6 @@ static int rcar_gen4_pcie_host_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);
 	int ret;
-	u32 val;
 
 	if (pp->bridge)
 		pp->bridge->enable_device = rcar_gen4_pcie_enable_device;
@@ -379,10 +425,7 @@ static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp)
 	dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_0, 0x0);
 	dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_1, 0x0);
 
-	/* Enable MSI interrupt signal */
-	val = readl(rcar->base + PCIEINTSTS0EN);
-	val |= MSI_CTRL_INT;
-	writel(val, rcar->base + PCIEINTSTS0EN);
+	rcar_gen4_pcie_host_msi_init(pp);
 
 	msleep(PCIE_T_PVPERL_MS);	/* pe_rst requires 100msec delay */
 
-- 
2.53.0

[PATCH 2/3] irqchip/gic-v3: Add Renesas R-Car Gen4 erratum workaround

[Marek Vasut]

Renesas R-Car S4/V4H/V4M GIC600 integration has address width for AXI
or APB interface configured to 32 bit, it can therefore access only
the first 4 GiB of physical address space. This information comes from
R-Car V4H Interface Specification sheet, there is currently no technical
update number assigned to this limitation. Further input from hardware
engineer indicates that this limitation also applies to R-Car S4 and V4M.
Name the limitation GEN4GICITS1, and add a driver quirk to mitigate this
limitation.

Note that the 0x0201743b GIC600 ID is not Renesas-specific, it is
common for many ARM GICv3 implementations. Therefore, add an extra
of_machine_is_compatible() check.

The GIC600 implementation in R-Car S4/V4H/V4M is r1p6.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
---
NOTE: This would not be possible without prior work from Shimoda-san
      https://lore.kernel.org/all/20240214052050.1966439-1-yoshihiro.shimoda.uh@renesas.com/
---
Cc: "Krzysztof Wilczyński" <kwilczynski@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-renesas-soc@vger.kernel.org
---
 Documentation/arch/arm64/silicon-errata.rst |  1 +
 arch/arm64/Kconfig                          |  9 +++++++++
 drivers/irqchip/irq-gic-v3-its.c            | 20 ++++++++++++++++++++
 3 files changed, 30 insertions(+)

diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst
index 014aa1c215a16..b0c68b64f5ac2 100644
--- a/Documentation/arch/arm64/silicon-errata.rst
+++ b/Documentation/arch/arm64/silicon-errata.rst
@@ -352,6 +352,7 @@ stable kernels.
 +----------------+-----------------+-----------------+-----------------------------+
 | Qualcomm Tech. | Kryo4xx Gold    | N/A             | ARM64_ERRATUM_1286807       |
 +----------------+-----------------+-----------------+-----------------------------+
+| Renesas        | S4/V4H/V4M      | N/A             | RENESAS_ERRATUM_GEN4GICITS1 |
 +----------------+-----------------+-----------------+-----------------------------+
 | Rockchip       | RK3588          | #3588001        | ROCKCHIP_ERRATUM_3588001    |
 +----------------+-----------------+-----------------+-----------------------------+
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b3afe0688919b..b9e17ce475e61 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1382,6 +1382,15 @@ config NVIDIA_CARMEL_CNP_ERRATUM
 
 	  If unsure, say Y.
 
+config RENESAS_ERRATUM_GEN4GICITS1
+	bool "Renesas R-Car Gen4: GIC600 can not access physical addresses above 4 GiB"
+	default y
+	help
+	  The Renesas R-Car Gen4 S4/V4H/V4M GIC600 SoC integrations have AXI
+	  addressing limited to the first 32-bit of physical address space.
+
+	  If unsure, say Y.
+
 config ROCKCHIP_ERRATUM_3568002
 	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
 	default y
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index b57d81ad33a0a..ec3756f29cf1a 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -4901,6 +4901,18 @@ static bool __maybe_unused its_enable_rk3568002(void *data)
 	return true;
 }
 
+static bool __maybe_unused its_enable_renesas_gen4(void *data)
+{
+	if (!of_machine_is_compatible("renesas,r8a779f0") &&
+	    !of_machine_is_compatible("renesas,r8a779g0") &&
+	    !of_machine_is_compatible("renesas,r8a779h0"))
+		return false;
+
+	gfp_flags_quirk |= GFP_DMA32;
+
+	return true;
+}
+
 static const struct gic_quirk its_quirks[] = {
 #ifdef CONFIG_CAVIUM_ERRATUM_22375
 	{
@@ -4975,6 +4987,14 @@ static const struct gic_quirk its_quirks[] = {
 		.mask   = 0xffffffff,
 		.init   = its_enable_rk3568002,
 	},
+#endif
+#ifdef CONFIG_RENESAS_ERRATUM_GEN4GICITS1
+	{
+		.desc   = "ITS: Renesas R-Car Gen4 GIC600 32-bit limit",
+		.iidr   = 0x0201743b,
+		.mask   = 0xffffffff,
+		.init   = its_enable_renesas_gen4,
+	},
 #endif
 	{
 	}
-- 
2.53.0

[PATCH 3/3] arm64: dts: renesas: r8a779g0: Add GICv3 ITS and update PCIe nodes

[Marek Vasut]

This SoC implements GIC600 with GICv3 ITS and PCIe host mode on this
SoC can use it. Add GIC ITS node into GIC node, update interrupt-map
and add msi-map into PCIe controller node.

The GIC ITS does have master interface to issue transactions to RAM.
The interface does support cacheable transactions, however, it does
not support shareable attribute, because the AXI port signals are tied
to inactive in this implementation. Therefore, add "dma-noncoherent"
DT property into the GIC ITS subnode.

The GIC redistributor does not have cacheable/shareable, therefore
add "dma-noncoherent" DT property into the GIC node.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
---
NOTE: This would not be possible without prior work from Shimoda-san
      https://lore.kernel.org/all/20240214052144.1966569-1-yoshihiro.shimoda.uh@renesas.com/
---
Cc: "Krzysztof Wilczyński" <kwilczynski@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-renesas-soc@vger.kernel.org
---
 arch/arm64/boot/dts/renesas/r8a779g0.dtsi | 31 ++++++++++++++++-------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/boot/dts/renesas/r8a779g0.dtsi b/arch/arm64/boot/dts/renesas/r8a779g0.dtsi
index 3a8af825bb253..82e864acf2601 100644
--- a/arch/arm64/boot/dts/renesas/r8a779g0.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a779g0.dtsi
@@ -792,6 +792,7 @@ pciec0: pcie@e65d0000 {
 			resets = <&cpg 624>;
 			reset-names = "pwr";
 			max-link-speed = <4>;
+			msi-parent = <&its>;
 			num-lanes = <2>;
 			#address-cells = <3>;
 			#size-cells = <2>;
@@ -802,10 +803,10 @@ pciec0: pcie@e65d0000 {
 			dma-ranges = <0x42000000 0 0x00000000 0 0x00000000 1 0x00000000>;
 			#interrupt-cells = <1>;
 			interrupt-map-mask = <0 0 0 7>;
-			interrupt-map = <0 0 0 1 &gic GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>,
-					<0 0 0 2 &gic GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>,
-					<0 0 0 3 &gic GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>,
-					<0 0 0 4 &gic GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-map = <0 0 0 1 &gic 0 0 GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>,
+					<0 0 0 2 &gic 0 0 GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>,
+					<0 0 0 3 &gic 0 0 GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>,
+					<0 0 0 4 &gic 0 0 GIC_SPI 449 IRQ_TYPE_LEVEL_HIGH>;
 			snps,enable-cdm-check;
 			status = "disabled";
 
@@ -839,6 +840,7 @@ pciec1: pcie@e65d8000 {
 			resets = <&cpg 625>;
 			reset-names = "pwr";
 			max-link-speed = <4>;
+			msi-parent = <&its>;
 			num-lanes = <2>;
 			#address-cells = <3>;
 			#size-cells = <2>;
@@ -849,10 +851,10 @@ pciec1: pcie@e65d8000 {
 			dma-ranges = <0x42000000 0 0x00000000 0 0x00000000 1 0x00000000>;
 			#interrupt-cells = <1>;
 			interrupt-map-mask = <0 0 0 7>;
-			interrupt-map = <0 0 0 1 &gic GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>,
-					<0 0 0 2 &gic GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>,
-					<0 0 0 3 &gic GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>,
-					<0 0 0 4 &gic GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-map = <0 0 0 1 &gic 0 0 GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>,
+					<0 0 0 2 &gic 0 0 GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>,
+					<0 0 0 3 &gic 0 0 GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>,
+					<0 0 0 4 &gic 0 0 GIC_SPI 456 IRQ_TYPE_LEVEL_HIGH>;
 			snps,enable-cdm-check;
 			status = "disabled";
 
@@ -2131,11 +2133,22 @@ ipmmu_mm: iommu@eefc0000 {
 		gic: interrupt-controller@f1000000 {
 			compatible = "arm,gic-v3";
 			#interrupt-cells = <3>;
-			#address-cells = <0>;
+			#address-cells = <2>;
+			#size-cells = <2>;
 			interrupt-controller;
 			reg = <0x0 0xf1000000 0 0x20000>,
 			      <0x0 0xf1060000 0 0x110000>;
 			interrupts = <GIC_PPI 9 IRQ_TYPE_LEVEL_HIGH>;
+			dma-noncoherent;
+
+			ranges = <0x0 0x0 0x0 0xf1000000 0x0 0x200000>;
+
+			its: msi-controller@40000 {
+				compatible = "arm,gic-v3-its";
+				reg = <0x0 0x40000 0x0 0x20000>;
+				dma-noncoherent;
+				msi-controller;
+			};
 		};
 
 		gpu: gpu@fd000000 {
-- 
2.53.0

Re: [PATCH 2/3] irqchip/gic-v3: Add Renesas R-Car Gen4 erratum workaround

[Geert Uytterhoeven]

Hi Marek,

On Wed, 17 Jun 2026 at 05:00, Marek Vasut
<marek.vasut+renesas@mailbox.org> wrote:
> Renesas R-Car S4/V4H/V4M GIC600 integration has address width for AXI
> or APB interface configured to 32 bit, it can therefore access only
> the first 4 GiB of physical address space. This information comes from
> R-Car V4H Interface Specification sheet, there is currently no technical
> update number assigned to this limitation. Further input from hardware
> engineer indicates that this limitation also applies to R-Car S4 and V4M.
> Name the limitation GEN4GICITS1, and add a driver quirk to mitigate this
> limitation.
>
> Note that the 0x0201743b GIC600 ID is not Renesas-specific, it is
> common for many ARM GICv3 implementations. Therefore, add an extra
> of_machine_is_compatible() check.
>
> The GIC600 implementation in R-Car S4/V4H/V4M is r1p6.
>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

Thanks for your patch!

> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -4901,6 +4901,18 @@ static bool __maybe_unused its_enable_rk3568002(void *data)
>         return true;
>  }
>
> +static bool __maybe_unused its_enable_renesas_gen4(void *data)
> +{
> +       if (!of_machine_is_compatible("renesas,r8a779f0") &&
> +           !of_machine_is_compatible("renesas,r8a779g0") &&
> +           !of_machine_is_compatible("renesas,r8a779h0"))

of_machine_compatible_match() with an array of strings might generate
smaller code (I didn't check if 3 entries is enough to trip the balance).

> +               return false;
> +
> +       gfp_flags_quirk |= GFP_DMA32;
> +
> +       return true;
> +}
> +
>  static const struct gic_quirk its_quirks[] = {
>  #ifdef CONFIG_CAVIUM_ERRATUM_22375
>         {

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 2/3] irqchip/gic-v3: Add Renesas R-Car Gen4 erratum workaround

[Marc Zyngier]

On Wed, 17 Jun 2026 03:59:45 +0100,
Marek Vasut <marek.vasut+renesas@mailbox.org> wrote:
> 
> Renesas R-Car S4/V4H/V4M GIC600 integration has address width for AXI
> or APB interface configured to 32 bit, it can therefore access only
> the first 4 GiB of physical address space. This information comes from
> R-Car V4H Interface Specification sheet, there is currently no technical
> update number assigned to this limitation. Further input from hardware
> engineer indicates that this limitation also applies to R-Car S4 and V4M.
> Name the limitation GEN4GICITS1, and add a driver quirk to mitigate this
> limitation.
> 
> Note that the 0x0201743b GIC600 ID is not Renesas-specific, it is
> common for many ARM GICv3 implementations. Therefore, add an extra

Not quite. It designates GIC600 unambiguously. It is just that GIC600
is integrated in zillions of SoCs, most of which don't have this
problem (the machine I'm typing this from has a GIC600 *and* 96GB of
RAM).

> of_machine_is_compatible() check.
> 
> The GIC600 implementation in R-Car S4/V4H/V4M is r1p6.

Is this relevant?

> 
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
> ---
> NOTE: This would not be possible without prior work from Shimoda-san
>       https://lore.kernel.org/all/20240214052050.1966439-1-yoshihiro.shimoda.uh@renesas.com/
> ---
> Cc: "Krzysztof Wilczyński" <kwilczynski@kernel.org>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
> Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
> Cc: Manivannan Sadhasivam <mani@kernel.org>
> Cc: Marc Zyngier <maz@kernel.org>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Cc: devicetree@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-doc@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-pci@vger.kernel.org
> Cc: linux-renesas-soc@vger.kernel.org
> ---
>  Documentation/arch/arm64/silicon-errata.rst |  1 +
>  arch/arm64/Kconfig                          |  9 +++++++++
>  drivers/irqchip/irq-gic-v3-its.c            | 20 ++++++++++++++++++++
>  3 files changed, 30 insertions(+)
> 
> diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst
> index 014aa1c215a16..b0c68b64f5ac2 100644
> --- a/Documentation/arch/arm64/silicon-errata.rst
> +++ b/Documentation/arch/arm64/silicon-errata.rst
> @@ -352,6 +352,7 @@ stable kernels.
>  +----------------+-----------------+-----------------+-----------------------------+
>  | Qualcomm Tech. | Kryo4xx Gold    | N/A             | ARM64_ERRATUM_1286807       |
>  +----------------+-----------------+-----------------+-----------------------------+
> +| Renesas        | S4/V4H/V4M      | N/A             | RENESAS_ERRATUM_GEN4GICITS1 |
>  +----------------+-----------------+-----------------+-----------------------------+
>  | Rockchip       | RK3588          | #3588001        | ROCKCHIP_ERRATUM_3588001    |
>  +----------------+-----------------+-----------------+-----------------------------+
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index b3afe0688919b..b9e17ce475e61 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1382,6 +1382,15 @@ config NVIDIA_CARMEL_CNP_ERRATUM
>  
>  	  If unsure, say Y.
>  
> +config RENESAS_ERRATUM_GEN4GICITS1
> +	bool "Renesas R-Car Gen4: GIC600 can not access physical addresses above 4 GiB"
> +	default y
> +	help
> +	  The Renesas R-Car Gen4 S4/V4H/V4M GIC600 SoC integrations have AXI
> +	  addressing limited to the first 32-bit of physical address space.
> +
> +	  If unsure, say Y.
> +
>  config ROCKCHIP_ERRATUM_3568002
>  	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
>  	default y
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index b57d81ad33a0a..ec3756f29cf1a 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -4901,6 +4901,18 @@ static bool __maybe_unused its_enable_rk3568002(void *data)
>  	return true;
>  }
>  
> +static bool __maybe_unused its_enable_renesas_gen4(void *data)
> +{
> +	if (!of_machine_is_compatible("renesas,r8a779f0") &&
> +	    !of_machine_is_compatible("renesas,r8a779g0") &&
> +	    !of_machine_is_compatible("renesas,r8a779h0"))
> +		return false;
> +
> +	gfp_flags_quirk |= GFP_DMA32;
> +
> +	return true;
> +}
> +
>  static const struct gic_quirk its_quirks[] = {
>  #ifdef CONFIG_CAVIUM_ERRATUM_22375
>  	{
> @@ -4975,6 +4987,14 @@ static const struct gic_quirk its_quirks[] = {
>  		.mask   = 0xffffffff,
>  		.init   = its_enable_rk3568002,
>  	},
> +#endif
> +#ifdef CONFIG_RENESAS_ERRATUM_GEN4GICITS1
> +	{
> +		.desc   = "ITS: Renesas R-Car Gen4 GIC600 32-bit limit",
> +		.iidr   = 0x0201743b,
> +		.mask   = 0xffffffff,
> +		.init   = its_enable_renesas_gen4,
> +	},
>  #endif
>  	{
>  	}


Honestly, that's a bit too much copy-paste for my taste. Just refactor
the erratum handling to be more generic, something like this:

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 291d7668cc8da..380c4758647d2 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -4894,10 +4894,17 @@ static bool __maybe_unused its_enable_quirk_hip09_162100801(void *data)
 	return true;
 }
 
-static bool __maybe_unused its_enable_rk3568002(void *data)
+static const char * const dma_impaired_platforms[] = {
+#ifdef CONFIG_ROCKCHIP_ERRATUM_3568002
+	"rockchip,rk3566",
+	"rockchip,rk3568",
+#endif
+	NULL,
+};
+
+static bool __maybe_unused its_enable_dma32(void *data)
 {
-	if (!of_machine_is_compatible("rockchip,rk3566") &&
-	    !of_machine_is_compatible("rockchip,rk3568"))
+	if (!of_machine_compatible_match(dma_impaired_platforms))
 		return false;
 
 	gfp_flags_quirk |= GFP_DMA32;
@@ -4972,14 +4979,12 @@ static const struct gic_quirk its_quirks[] = {
 		.property = "dma-noncoherent",
 		.init   = its_set_non_coherent,
 	},
-#ifdef CONFIG_ROCKCHIP_ERRATUM_3568002
 	{
-		.desc   = "ITS: Rockchip erratum RK3568002",
+		.desc   = "ITS: Broken GIC600 integration limited to 32bit PA",
 		.iidr   = 0x0201743b,
 		.mask   = 0xffffffff,
-		.init   = its_enable_rk3568002,
+		.init   = its_enable_dma32,
 	},
-#endif
 	{
 	}
 };

Then add the two lines you need in a separate patch.

In the future, please provide a cover letter when you have more than a
single patch (git will happily generate one for you).

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.

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

[Marc Zyngier]

On Wed, 17 Jun 2026 03:59:44 +0100,
Marek Vasut <marek.vasut+renesas@mailbox.org> wrote:
> 
> In case MSI are enabled, but DWC built-in iMSI-RX is not in use, the
> MSI are handled via GIC ITS. Configure all controller MSI registers
> fully.
> 
> Set or clear MSI capability register MSICAP0 MSI enable MSIE bit and
> PCIe Interrupt Status 0 Enable register PCIEINTSTS0EN MSI interrupt
> enable MSI_CTRL_INT bit according to MSI enable state, set both bits
> if MSI are enabled, clear both bits if MSI are disabled.
> 
> If MSI are disabled, or MSI are enabled and iMSI-RX is used, then
> deconfigure AXIINTCADDR and AXIINTCCONT to 0, which disables any
> pass through of MSI TLPs onto the AXI bus and then further into
> GIC ITS translation registers.
> 
> If MSI are enabled and iMSI-RX is not used, the configure AXIINTCADDR
> with target address of GIC ITS translation registers, and configure
> AXIINTCCONT to enable MSI TLP pass through onto AXI bus and into the
> GIC ITS. This specific configuration allows handling of MSI via the
> GIC ITS instead of integrated iMSI-RX.
> 
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
> ---
> NOTE: This would not be possible without prior work from Shimoda-san
> ---
> Cc: "Krzysztof Wilczyński" <kwilczynski@kernel.org>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
> Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
> Cc: Manivannan Sadhasivam <mani@kernel.org>
> Cc: Marc Zyngier <maz@kernel.org>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Cc: devicetree@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-doc@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-pci@vger.kernel.org
> Cc: linux-renesas-soc@vger.kernel.org
> ---
>  drivers/pci/controller/dwc/pcie-rcar-gen4.c | 53 +++++++++++++++++++--
>  1 file changed, 48 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index 485cfa8bd9692..ba6e3bedd6d0a 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -31,6 +31,10 @@
>  #define DEVICE_TYPE_RC		BIT(4)
>  #define BIFUR_MOD_SET_ON	BIT(0)
>  
> +/* MSI Capability */
> +#define MSICAP0			0x0050
> +#define MSICAP0_MSIE		BIT(16)
> +
>  /* PCIe Interrupt Status 0 */
>  #define PCIEINTSTS0		0x0084
>  
> @@ -55,6 +59,16 @@
>  #define APP_HOLD_PHY_RST	BIT(16)
>  #define APP_LTSSM_ENABLE	BIT(0)
>  
> +/* INTC address */
> +#define AXIINTCADDR		0x0a00
> +/* GITS GIC ITS translation register */
> +#define AXIINTCADDR_VAL		0xf1050000

Wouldn't it be preferable to source the address from the device tree,
rather than hardcoding this?

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.

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

[Geert Uytterhoeven]

Hi Marek,

On Wed, 17 Jun 2026 at 05:00, Marek Vasut
<marek.vasut+renesas@mailbox.org> wrote:
> In case MSI are enabled, but DWC built-in iMSI-RX is not in use, the
> MSI are handled via GIC ITS. Configure all controller MSI registers
> fully.
>
> Set or clear MSI capability register MSICAP0 MSI enable MSIE bit and
> PCIe Interrupt Status 0 Enable register PCIEINTSTS0EN MSI interrupt
> enable MSI_CTRL_INT bit according to MSI enable state, set both bits
> if MSI are enabled, clear both bits if MSI are disabled.
>
> If MSI are disabled, or MSI are enabled and iMSI-RX is used, then
> deconfigure AXIINTCADDR and AXIINTCCONT to 0, which disables any
> pass through of MSI TLPs onto the AXI bus and then further into
> GIC ITS translation registers.
>
> If MSI are enabled and iMSI-RX is not used, the configure AXIINTCADDR
> with target address of GIC ITS translation registers, and configure
> AXIINTCCONT to enable MSI TLP pass through onto AXI bus and into the
> GIC ITS. This specific configuration allows handling of MSI via the
> GIC ITS instead of integrated iMSI-RX.
>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

Thanks for your patch!

> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -31,6 +31,10 @@
>  #define DEVICE_TYPE_RC         BIT(4)
>  #define BIFUR_MOD_SET_ON       BIT(0)
>
> +/* MSI Capability */
> +#define MSICAP0                        0x0050
> +#define MSICAP0_MSIE           BIT(16)
> +
>  /* PCIe Interrupt Status 0 */
>  #define PCIEINTSTS0            0x0084
>
> @@ -55,6 +59,16 @@
>  #define APP_HOLD_PHY_RST       BIT(16)
>  #define APP_LTSSM_ENABLE       BIT(0)
>
> +/* INTC address */
> +#define AXIINTCADDR            0x0a00
> +/* GITS GIC ITS translation register */
> +#define AXIINTCADDR_VAL                0xf1050000
> +
> +/* INTC control & mask */
> +#define AXIINTCCONT            0x0a04
> +#define INTC_EN                        BIT(31)
> +#define INTC_MASK              GENMASK(11, 2)
> +
>  /* PCIe Power Management Control */
>  #define PCIEPWRMNGCTRL         0x0070
>  #define APP_CLK_REQ_N          BIT(11)
> @@ -305,6 +319,39 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
>         return rcar;
>  }
>
> +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@mailbox.org).

>                                         struct pci_dev *dev)
>  {

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

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

[Manivannan Sadhasivam]

On Wed, Jun 17, 2026 at 04:59:44AM +0200, Marek Vasut wrote:
> In case MSI are enabled, but DWC built-in iMSI-RX is not in use, the
> MSI are handled via GIC ITS. Configure all controller MSI registers
> fully.
> 
> Set or clear MSI capability register MSICAP0 MSI enable MSIE bit and
> PCIe Interrupt Status 0 Enable register PCIEINTSTS0EN MSI interrupt
> enable MSI_CTRL_INT bit according to MSI enable state, set both bits
> if MSI are enabled, clear both bits if MSI are disabled.
> 
> If MSI are disabled, or MSI are enabled and iMSI-RX is used, then
> deconfigure AXIINTCADDR and AXIINTCCONT to 0, which disables any
> pass through of MSI TLPs onto the AXI bus and then further into
> GIC ITS translation registers.
> 
> If MSI are enabled and iMSI-RX is not used, the configure AXIINTCADDR
> with target address of GIC ITS translation registers, and configure
> AXIINTCCONT to enable MSI TLP pass through onto AXI bus and into the
> GIC ITS. This specific configuration allows handling of MSI via the
> GIC ITS instead of integrated iMSI-RX.
> 
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
> ---
> NOTE: This would not be possible without prior work from Shimoda-san
> ---
> Cc: "Krzysztof Wilczyński" <kwilczynski@kernel.org>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
> Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
> Cc: Manivannan Sadhasivam <mani@kernel.org>
> Cc: Marc Zyngier <maz@kernel.org>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Cc: devicetree@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-doc@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-pci@vger.kernel.org
> Cc: linux-renesas-soc@vger.kernel.org
> ---
>  drivers/pci/controller/dwc/pcie-rcar-gen4.c | 53 +++++++++++++++++++--
>  1 file changed, 48 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index 485cfa8bd9692..ba6e3bedd6d0a 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -31,6 +31,10 @@
>  #define DEVICE_TYPE_RC		BIT(4)
>  #define BIFUR_MOD_SET_ON	BIT(0)
>  
> +/* MSI Capability */
> +#define MSICAP0			0x0050
> +#define MSICAP0_MSIE		BIT(16)
> +
>  /* PCIe Interrupt Status 0 */
>  #define PCIEINTSTS0		0x0084
>  
> @@ -55,6 +59,16 @@
>  #define APP_HOLD_PHY_RST	BIT(16)
>  #define APP_LTSSM_ENABLE	BIT(0)
>  
> +/* INTC address */
> +#define AXIINTCADDR		0x0a00
> +/* GITS GIC ITS translation register */
> +#define AXIINTCADDR_VAL		0xf1050000

As Marc pointed out, this address should be fetched from DT, not hardcoded in
the driver.

> +
> +/* INTC control & mask */
> +#define AXIINTCCONT		0x0a04
> +#define INTC_EN			BIT(31)
> +#define INTC_MASK		GENMASK(11, 2)
> +
>  /* PCIe Power Management Control */
>  #define PCIEPWRMNGCTRL		0x0070
>  #define APP_CLK_REQ_N		BIT(11)
> @@ -305,6 +319,39 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
>  	return rcar;
>  }
>  
> +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) {

If MSI is not enabled, then what's the point in clearing these registers (also
above)? I see it as a redundant code. Is there a necessity to clear them?

- Mani

-- 
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