[PATCH v4 0/2] pci: AMD: Add Versal2 CPM6 PCIe host controller support

[PATCH v4 0/2] pci: AMD: Add Versal2 CPM6 PCIe host controller support

[Sai Krishna Musham]

Add support for the AMD Versal2 CPM6 PCIe host controller to the
AMD MDB PCIe driver.

Sai Krishna Musham (2):
  dt-bindings: PCI: amd-mdb: Add CPM6 support
  PCI: amd-mdb: Add CPM6 host controller support

 .../bindings/pci/amd,versal2-mdb-host.yaml    |  45 +-
 .../devicetree/bindings/pci/snps,dw-pcie.yaml |   2 +
 drivers/pci/controller/dwc/pcie-amd-mdb.c     | 424 +++++++++++++++---
 3 files changed, 405 insertions(+), 66 deletions(-)


base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
-- 
2.44.4

[PATCH v4 1/2] dt-bindings: PCI: amd-mdb: Add CPM6 support

[Sai Krishna Musham]

The AMD CPM6 PCIe controller is based on the Synopsys DesignWare PCIe IP.
Add "intr" to snps,dw-pcie.yaml vendor-specific reg-names for the
per-controller interrupt register region used by CPM6.

Update amd,versal2-mdb-host.yaml with separate register definitions:
- MDB5: 4 regions (slcr, config, dbi, atu)
- CPM6: 5 regions (slcr, config, dbi, atu, intr)

Signed-off-by: Sai Krishna Musham <sai.krishna.musham@amd.com>
---
Changes in v4:
- None

Changes in v3:
- Update subject to match history.
- Move allOf to the end, after required block.
- Drop the CPM6 example.

Changes in v2:
- Update the CPM6 device tree binding and example.

v1 https://lore.kernel.org/all/20260402180006.486229-2-sai.krishna.musham@amd.com/
v2 https://lore.kernel.org/all/20260728202044.1785986-2-sai.krishna.musham@amd.com/
v3 https://lore.kernel.org/all/20260803144412.713639-2-sai.krishna.musham@amd.com/
---
 .../bindings/pci/amd,versal2-mdb-host.yaml    | 45 ++++++++++++++++---
 .../devicetree/bindings/pci/snps,dw-pcie.yaml |  2 +
 2 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml b/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml
index 406c15e1dee1..672589066854 100644
--- a/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml
+++ b/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml
@@ -9,27 +9,30 @@ title: AMD Versal2 MDB(Multimedia DMA Bridge) Host Controller
 maintainers:
   - Thippeswamy Havalige <thippeswamy.havalige@amd.com>
 
-allOf:
-  - $ref: /schemas/pci/pci-host-bridge.yaml#
-  - $ref: /schemas/pci/snps,dw-pcie.yaml#
-
 properties:
   compatible:
-    const: amd,versal2-mdb-host
+    enum:
+      - amd,versal2-mdb-host
+      - amd,versal2-cpm6-host
+      - amd,versal2-cpm6-host1
 
   reg:
+    minItems: 4
     items:
       - description: MDB System Level Control and Status Register (SLCR) Base
       - description: configuration region
       - description: data bus interface
       - description: address translation unit register
+      - description: CPM6 PCIe error and event interrupt registers
 
   reg-names:
+    minItems: 4
     items:
       - const: slcr
       - const: config
       - const: dbi
       - const: atu
+      - const: intr
 
   ranges:
     maxItems: 2
@@ -92,6 +95,38 @@ required:
   - "#interrupt-cells"
   - interrupt-controller
 
+allOf:
+  - $ref: /schemas/pci/pci-host-bridge.yaml#
+  - $ref: /schemas/pci/snps,dw-pcie.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: amd,versal2-mdb-host
+    then:
+      properties:
+        reg:
+          minItems: 4
+          maxItems: 4
+        reg-names:
+          minItems: 4
+          maxItems: 4
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - amd,versal2-cpm6-host
+              - amd,versal2-cpm6-host1
+    then:
+      properties:
+        reg:
+          minItems: 5
+          maxItems: 5
+        reg-names:
+          minItems: 5
+          maxItems: 5
+
 unevaluatedProperties: false
 
 examples:
diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
index b3216141881c..21f86609ddb6 100644
--- a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
@@ -117,6 +117,8 @@ properties:
               enum: [ ecam ]
             - description: AMD MDB PCIe SLCR region
               const: slcr
+            - description: AMD CPM6 PCIe error and event interrupt registers
+              const: intr
     allOf:
       - contains:
           enum: [ dbi, ctrl ]
-- 
2.44.4

[PATCH v4 2/2] PCI: amd-mdb: Add CPM6 host controller support

[Sai Krishna Musham]

Extend the AMD MDB PCIe driver to support AMD Versal2 CPM6 variants
(amd,versal2-cpm6-host and amd,versal2-cpm6-host1). Like MDB5, CPM6 is
based on the Synopsys DesignWare PCIe controller and reuses the existing
DesignWare host support; only the interrupt architecture differs:
- The per-controller interrupt registers (MISC_EVENT, PCIE_ERR) are in a
  dedicated "intr" region instead of the shared SLCR
- The aggregation layer (MERGED, PS_MISC) is shared and sticky; it
  requires an explicit W1C-clear after servicing to prevent IRQ storms
- The completion timeout is reported via PCIE_ERR instead of MISC_EVENT

Add variant-specific register layout and implement aggregator clearing
that, after every interrupt pass, clears this host's contribution from
the MERGED register and the corresponding bit in the PS_MISC severity
register.

Signed-off-by: Sai Krishna Musham <sai.krishna.musham@amd.com>
---
Changes in v4:
- Use IRQF_SHARED for the CPM6 event IRQ since the misc/error GIC line
  is shared between both host controllers.
- Read PCIE_ERR before servicing MISC_EVENT to snapshot the error state
  before it is cleared.

Changes in v3:
- Add missing completion-timeout handling via PCIE_ERR.
- Add CPM6 INTx shared-enable refcount handling (mask/unmask via intx_refmask).
- Fix probe-failure cleanup to avoid double-free/use-after-free risk.
- Fix CPM6 slcr mapping to use non-exclusive ioremap for shared SLCR.
- Clear unhandled asserted bits in AMD_CPM6_PCIE_ERR_STATUS.

Changes in v2:
- Add CPM6 host controller interrupt support.

v1 https://lore.kernel.org/all/20260402180006.486229-3-sai.krishna.musham@amd.com/
v2 https://lore.kernel.org/all/20260728202044.1785986-3-sai.krishna.musham@amd.com/
v3 https://lore.kernel.org/all/20260803144412.713639-3-sai.krishna.musham@amd.com/
---
 drivers/pci/controller/dwc/pcie-amd-mdb.c | 424 ++++++++++++++++++----
 1 file changed, 363 insertions(+), 61 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-amd-mdb.c b/drivers/pci/controller/dwc/pcie-amd-mdb.c
index dee295f281a3..3e8e02ab96bc 100644
--- a/drivers/pci/controller/dwc/pcie-amd-mdb.c
+++ b/drivers/pci/controller/dwc/pcie-amd-mdb.c
@@ -21,6 +21,23 @@
 #include "../../pci.h"
 #include "pcie-designware.h"
 
+/*
+ * On CPM6 the per-controller PCIe interrupt registers (MISC_EVENT and
+ * PCIE_ERR) live in a dedicated region ("intr"), separate from the CPM SLCR
+ * region ("slcr") that holds the MERGED and PS severity registers they feed
+ * into. Each has a sticky W1C STATUS, a read-only MASK, and write-1
+ * ENABLE/DISABLE register.
+ */
+#define AMD_CPM6_PCIE_ERR_STATUS		0x500
+#define AMD_CPM6_PCIE_ERR_MASK			0x504
+#define AMD_CPM6_PCIE_ERR_ENABLE		0x508
+#define AMD_CPM6_PCIE_ERR_DISABLE		0x50C
+
+#define AMD_CPM6_MISC_EVENT_STATUS		0x514
+#define AMD_CPM6_MISC_EVENT_MASK		0x518
+#define AMD_CPM6_MISC_EVENT_ENABLE		0x51C
+#define AMD_CPM6_MISC_EVENT_DISABLE		0x520
+
 #define AMD_MDB_TLP_IR_STATUS_MISC		0x4C0
 #define AMD_MDB_TLP_IR_MASK_MISC		0x4C4
 #define AMD_MDB_TLP_IR_ENABLE_MISC		0x4C8
@@ -30,7 +47,23 @@
 
 #define AMD_MDB_PCIE_INTR_INTX_ASSERT(x)	BIT((x) * 2)
 
-/* Interrupt registers definitions. */
+#define AMD_CPM6_MERGED_STATUS			0x648
+#define AMD_CPM6_MERGED_ENABLE			0x650
+
+/* MERGED input bits for the MISC_EVENT/PCIE_ERR sources this driver handles. */
+#define AMD_CPM6_MERGED_PCIE_ERR_HOST0		13
+#define AMD_CPM6_MERGED_MISC_EVENT_HOST0	14
+#define AMD_CPM6_MERGED_PCIE_ERR_HOST1		16
+#define AMD_CPM6_MERGED_MISC_EVENT_HOST1	17
+
+/*
+ * The PS_MISC severity register feeds the misc/OR GIC line. The MERGED
+ * aggregator appears as bit 21 within it.
+ */
+#define AMD_CPM6_PS_MISC_IR_STATUS		0x340
+#define AMD_CPM6_PS_IR_MERGED		BIT(21)
+
+/* MDB5 interrupt register definitions. */
 #define AMD_MDB_PCIE_INTR_CMPL_TIMEOUT		15
 #define AMD_MDB_PCIE_INTR_INTX			16
 #define AMD_MDB_PCIE_INTR_PM_PME_RCVD		24
@@ -39,6 +72,9 @@
 #define AMD_MDB_PCIE_INTR_NONFATAL		27
 #define AMD_MDB_PCIE_INTR_FATAL			28
 
+/* Completion timeout lives in PCIE_ERR_STATUS; give it a dedicated hwirq. */
+#define AMD_CPM6_PCIE_ERR_CMPL_RADM		20
+
 #define IMR(x) BIT(AMD_MDB_PCIE_INTR_ ##x)
 #define AMD_MDB_PCIE_IMR_ALL_MASK			\
 	(						\
@@ -51,24 +87,133 @@
 		AMD_MDB_TLP_PCIE_INTX_MASK		\
 	)
 
+/* CPM6 hwirq mapping (hwirq == MISC_EVENT status bit). */
+#define AMD_CPM6_PCIE_INTR_FATAL		17
+#define AMD_CPM6_PCIE_INTR_NONFATAL		18
+#define AMD_CPM6_PCIE_INTR_MISC_CORRECTABLE	19
+#define AMD_CPM6_PCIE_INTR_PME_TO_ACK_RCVD	20
+#define AMD_CPM6_PCIE_INTR_PM_PME_RCVD		21
+#define AMD_CPM6_PCIE_INTR_INTX			22
+
+/* Map the PCIE_ERR completion timeout onto an event-domain hwirq. */
+#define AMD_CPM6_PCIE_INTR_CMPL_TIMEOUT		15
+
+#define AMD_CPM6_MISC_EVENT_MASK_ALL					\
+	(								\
+		BIT(AMD_CPM6_PCIE_INTR_FATAL)			|	\
+		BIT(AMD_CPM6_PCIE_INTR_NONFATAL)		|	\
+		BIT(AMD_CPM6_PCIE_INTR_MISC_CORRECTABLE)	|	\
+		BIT(AMD_CPM6_PCIE_INTR_PME_TO_ACK_RCVD)		|	\
+		BIT(AMD_CPM6_PCIE_INTR_PM_PME_RCVD)		|	\
+		BIT(AMD_CPM6_PCIE_INTR_INTX)				\
+	)
+
+/* Sources handled in the PCIE_ERR register. */
+#define AMD_CPM6_PCIE_ERR_MASK_ALL	BIT(AMD_CPM6_PCIE_ERR_CMPL_RADM)
+
+enum amd_mdb_pcie_version {
+	MDB5,
+	CPM6,
+	CPM6_HOST1,
+};
+
+struct amd_mdb_intr_cause {
+	const char	*sym;
+	const char	*str;
+};
+
+struct amd_mdb_pcie_variant {
+	enum	amd_mdb_pcie_version version;
+	u32	misc_status_reg;
+	u32	misc_mask_reg;
+	u32	misc_enable_reg;
+	u32	misc_disable_reg;
+	u32	misc_mask_all;
+	u32	intx_hwirq;
+	u32	intx_mask;
+};
+
 /**
  * struct amd_mdb_pcie - PCIe port information
  * @pci: DesignWare PCIe controller structure
  * @slcr: MDB System Level Control and Status Register (SLCR) base
+ * @intr_base: Per-controller interrupt register base. On CPM6 this maps the
+ *             "intr" region holding the MISC_EVENT/PCIE_ERR registers; on MDB5
+ *             the interrupt registers live in the SLCR block, so it aliases
+ *             @slcr.
+ * @variant: Interrupt layout data for the matched platform compatible
  * @intx_domain: INTx IRQ domain pointer
  * @mdb_domain: MDB IRQ domain pointer
  * @perst_gpio: GPIO descriptor for PERST# signal handling
  * @intx_irq: INTx IRQ interrupt number
+ * @intx_refmask: CPM6 mask of unmasked INTx lines; gates the shared aggregate
  */
 struct amd_mdb_pcie {
 	struct dw_pcie			pci;
 	void __iomem			*slcr;
+	void __iomem			*intr_base;
+	const struct amd_mdb_pcie_variant	*variant;
 	struct irq_domain		*intx_domain;
 	struct irq_domain		*mdb_domain;
 	struct gpio_desc		*perst_gpio;
 	int				intx_irq;
+	u32				intx_refmask;
+};
+
+#define _IC(x, s)[AMD_MDB_PCIE_INTR_ ## x] = { __stringify(x), s }
+
+static const struct amd_mdb_intr_cause mdb5_intr_cause[32] = {
+	_IC(CMPL_TIMEOUT,	"Completion timeout"),
+	_IC(PM_PME_RCVD,	"PM_PME message received"),
+	_IC(PME_TO_ACK_RCVD,	"PME_TO_ACK message received"),
+	_IC(MISC_CORRECTABLE,	"Correctable error message"),
+	_IC(NONFATAL,		"Non fatal error message"),
+	_IC(FATAL,		"Fatal error message"),
+};
+
+#define _IC6(x, s)[AMD_CPM6_PCIE_INTR_ ## x] = { __stringify(x), s }
+
+static const struct amd_mdb_intr_cause cpm6_intr_cause[32] = {
+	_IC6(CMPL_TIMEOUT,	"Completion timeout"),
+	_IC6(PM_PME_RCVD,	"PM_PME message received"),
+	_IC6(PME_TO_ACK_RCVD,	"PME_TO_ACK message received"),
+	_IC6(MISC_CORRECTABLE,	"Correctable error message"),
+	_IC6(NONFATAL,		"Non fatal error message"),
+	_IC6(FATAL,		"Fatal error message"),
 };
 
+/* Both cause tables are indexed by hwirq, so they must be the same size. */
+static_assert(ARRAY_SIZE(mdb5_intr_cause) == ARRAY_SIZE(cpm6_intr_cause));
+
+static u32 amd_mdb_pcie_merged_host_mask(struct amd_mdb_pcie *pcie)
+{
+	return pcie->variant->version == CPM6 ?
+	       BIT(AMD_CPM6_MERGED_MISC_EVENT_HOST0) |
+	       BIT(AMD_CPM6_MERGED_PCIE_ERR_HOST0) :
+	       BIT(AMD_CPM6_MERGED_MISC_EVENT_HOST1) |
+	       BIT(AMD_CPM6_MERGED_PCIE_ERR_HOST1);
+}
+
+static void amd_mdb_pcie_clear_aggregators(struct amd_mdb_pcie *pcie)
+{
+	if (pcie->variant->version == MDB5)
+		return;
+
+	/*
+	 * Clear this host's serviced contributions (MISC_EVENT and PCIE_ERR)
+	 * from MERGED.
+	 */
+	writel_relaxed(amd_mdb_pcie_merged_host_mask(pcie),
+		       pcie->slcr + AMD_CPM6_MERGED_STATUS);
+
+	/*
+	 * Clear MERGED in the PS_MISC severity register so the misc GIC line
+	 * de-asserts.
+	 */
+	writel_relaxed(AMD_CPM6_PS_IR_MERGED,
+		       pcie->slcr + AMD_CPM6_PS_MISC_IR_STATUS);
+}
+
 static const struct dw_pcie_host_ops amd_mdb_pcie_host_ops = {
 };
 
@@ -81,14 +226,21 @@ static void amd_mdb_intx_irq_mask(struct irq_data *data)
 	u32 val;
 
 	raw_spin_lock_irqsave(&port->lock, flags);
-	val = FIELD_PREP(AMD_MDB_TLP_PCIE_INTX_MASK,
-			 AMD_MDB_PCIE_INTR_INTX_ASSERT(data->hwirq));
-
-	/*
-	 * Writing '1' to a bit in AMD_MDB_TLP_IR_DISABLE_MISC disables that
-	 * interrupt, writing '0' has no effect.
-	 */
-	writel_relaxed(val, pcie->slcr + AMD_MDB_TLP_IR_DISABLE_MISC);
+	if (pcie->variant->version == MDB5) {
+		val = FIELD_PREP(AMD_MDB_TLP_PCIE_INTX_MASK,
+				 AMD_MDB_PCIE_INTR_INTX_ASSERT(data->hwirq));
+		/*
+		 * Writing '1' to a bit in AMD_MDB_TLP_IR_DISABLE_MISC disables
+		 * that interrupt, writing '0' has no effect.
+		 */
+		writel_relaxed(val, pcie->intr_base + pcie->variant->misc_disable_reg);
+	} else {
+		/* CPM6 shares one INTx enable; drop it on the last mask. */
+		pcie->intx_refmask &= ~BIT(data->hwirq);
+		if (!pcie->intx_refmask)
+			writel_relaxed(pcie->variant->intx_mask,
+				       pcie->intr_base + pcie->variant->misc_disable_reg);
+	}
 	raw_spin_unlock_irqrestore(&port->lock, flags);
 }
 
@@ -101,14 +253,21 @@ static void amd_mdb_intx_irq_unmask(struct irq_data *data)
 	u32 val;
 
 	raw_spin_lock_irqsave(&port->lock, flags);
-	val = FIELD_PREP(AMD_MDB_TLP_PCIE_INTX_MASK,
-			 AMD_MDB_PCIE_INTR_INTX_ASSERT(data->hwirq));
-
-	/*
-	 * Writing '1' to a bit in AMD_MDB_TLP_IR_ENABLE_MISC enables that
-	 * interrupt, writing '0' has no effect.
-	 */
-	writel_relaxed(val, pcie->slcr + AMD_MDB_TLP_IR_ENABLE_MISC);
+	if (pcie->variant->version == MDB5) {
+		val = FIELD_PREP(AMD_MDB_TLP_PCIE_INTX_MASK,
+				 AMD_MDB_PCIE_INTR_INTX_ASSERT(data->hwirq));
+		/*
+		 * Writing '1' to a bit in AMD_MDB_TLP_IR_ENABLE_MISC enables
+		 * that interrupt, writing '0' has no effect.
+		 */
+		writel_relaxed(val, pcie->intr_base + pcie->variant->misc_enable_reg);
+	} else {
+		/* CPM6 shares one INTx enable; raise it on the first unmask. */
+		if (!pcie->intx_refmask)
+			writel_relaxed(pcie->variant->intx_mask,
+				       pcie->intr_base + pcie->variant->misc_enable_reg);
+		pcie->intx_refmask |= BIT(data->hwirq);
+	}
 	raw_spin_unlock_irqrestore(&port->lock, flags);
 }
 
@@ -148,42 +307,40 @@ static irqreturn_t dw_pcie_rp_intx(int irq, void *args)
 	unsigned long val;
 	int i, int_status;
 
-	val = readl_relaxed(pcie->slcr + AMD_MDB_TLP_IR_STATUS_MISC);
-	int_status = FIELD_GET(AMD_MDB_TLP_PCIE_INTX_MASK, val);
+	val = readl_relaxed(pcie->intr_base + pcie->variant->misc_status_reg);
 
-	for (i = 0; i < PCI_NUM_INTX; i++) {
-		if (int_status & AMD_MDB_PCIE_INTR_INTX_ASSERT(i))
+	if (pcie->variant->version == MDB5) {
+		int_status = FIELD_GET(AMD_MDB_TLP_PCIE_INTX_MASK, val);
+		for (i = 0; i < PCI_NUM_INTX; i++) {
+			if (int_status & AMD_MDB_PCIE_INTR_INTX_ASSERT(i))
+				generic_handle_domain_irq(pcie->intx_domain, i);
+		}
+	} else {
+		/* CPM6 exposes only an aggregate INTx indication */
+		if (!(val & pcie->variant->intx_mask))
+			return IRQ_NONE;
+		for (i = 0; i < PCI_NUM_INTX; i++)
 			generic_handle_domain_irq(pcie->intx_domain, i);
 	}
 
 	return IRQ_HANDLED;
 }
 
-#define _IC(x, s)[AMD_MDB_PCIE_INTR_ ## x] = { __stringify(x), s }
-
-static const struct {
-	const char	*sym;
-	const char	*str;
-} intr_cause[32] = {
-	_IC(CMPL_TIMEOUT,	"Completion timeout"),
-	_IC(PM_PME_RCVD,	"PM_PME message received"),
-	_IC(PME_TO_ACK_RCVD,	"PME_TO_ACK message received"),
-	_IC(MISC_CORRECTABLE,	"Correctable error message"),
-	_IC(NONFATAL,		"Non fatal error message"),
-	_IC(FATAL,		"Fatal error message"),
-};
-
 static void amd_mdb_event_irq_mask(struct irq_data *d)
 {
 	struct amd_mdb_pcie *pcie = irq_data_get_irq_chip_data(d);
 	struct dw_pcie *pci = &pcie->pci;
 	struct dw_pcie_rp *port = &pci->pp;
 	unsigned long flags;
-	u32 val;
 
 	raw_spin_lock_irqsave(&port->lock, flags);
-	val = BIT(d->hwirq);
-	writel_relaxed(val, pcie->slcr + AMD_MDB_TLP_IR_DISABLE_MISC);
+	if (pcie->variant->version != MDB5 &&
+	    d->hwirq == AMD_CPM6_PCIE_INTR_CMPL_TIMEOUT)
+		writel_relaxed(AMD_CPM6_PCIE_ERR_MASK_ALL,
+			       pcie->intr_base + AMD_CPM6_PCIE_ERR_DISABLE);
+	else
+		writel_relaxed(BIT(d->hwirq),
+			       pcie->intr_base + pcie->variant->misc_disable_reg);
 	raw_spin_unlock_irqrestore(&port->lock, flags);
 }
 
@@ -193,11 +350,15 @@ static void amd_mdb_event_irq_unmask(struct irq_data *d)
 	struct dw_pcie *pci = &pcie->pci;
 	struct dw_pcie_rp *port = &pci->pp;
 	unsigned long flags;
-	u32 val;
 
 	raw_spin_lock_irqsave(&port->lock, flags);
-	val = BIT(d->hwirq);
-	writel_relaxed(val, pcie->slcr + AMD_MDB_TLP_IR_ENABLE_MISC);
+	if (pcie->variant->version != MDB5 &&
+	    d->hwirq == AMD_CPM6_PCIE_INTR_CMPL_TIMEOUT)
+		writel_relaxed(AMD_CPM6_PCIE_ERR_MASK_ALL,
+			       pcie->intr_base + AMD_CPM6_PCIE_ERR_ENABLE);
+	else
+		writel_relaxed(BIT(d->hwirq),
+			       pcie->intr_base + pcie->variant->misc_enable_reg);
 	raw_spin_unlock_irqrestore(&port->lock, flags);
 }
 
@@ -226,13 +387,44 @@ static irqreturn_t amd_mdb_pcie_event(int irq, void *args)
 {
 	struct amd_mdb_pcie *pcie = args;
 	unsigned long val;
+	u32 ev_raw, err;
 	int i;
 
-	val = readl_relaxed(pcie->slcr + AMD_MDB_TLP_IR_STATUS_MISC);
-	val &= ~readl_relaxed(pcie->slcr + AMD_MDB_TLP_IR_MASK_MISC);
+	ev_raw = readl_relaxed(pcie->intr_base + pcie->variant->misc_status_reg);
+	val = ev_raw;
+	val &= ~readl_relaxed(pcie->intr_base + pcie->variant->misc_mask_reg);
+
+	if (pcie->variant->version == MDB5) {
+		for_each_set_bit(i, &val, 32)
+			generic_handle_domain_irq(pcie->mdb_domain, i);
+		writel_relaxed(val, pcie->intr_base + pcie->variant->misc_status_reg);
+		return IRQ_HANDLED;
+	}
+
+	err = readl_relaxed(pcie->intr_base + AMD_CPM6_PCIE_ERR_STATUS);
+
+	val &= pcie->variant->misc_mask_all;
+
 	for_each_set_bit(i, &val, 32)
 		generic_handle_domain_irq(pcie->mdb_domain, i);
-	writel_relaxed(val, pcie->slcr + AMD_MDB_TLP_IR_STATUS_MISC);
+
+	/* Clear handled + any unhandled sticky bits to avoid IRQ storms. */
+	writel_relaxed(ev_raw, pcie->intr_base + pcie->variant->misc_status_reg);
+
+	/* On CPM6 completion timeout is reported via PCIE_ERR. */
+	if (err) {
+		u32 pending = err & ~readl_relaxed(pcie->intr_base +
+						   AMD_CPM6_PCIE_ERR_MASK);
+
+		if (pending & AMD_CPM6_PCIE_ERR_MASK_ALL)
+			generic_handle_domain_irq(pcie->mdb_domain,
+						  AMD_CPM6_PCIE_INTR_CMPL_TIMEOUT);
+		/* Clear every asserted bit so the leaf and MERGED de-assert. */
+		writel_relaxed(err, pcie->intr_base + AMD_CPM6_PCIE_ERR_STATUS);
+	}
+
+	/* Sticky aggregation bits; clear each pass or the IRQ re-fires */
+	amd_mdb_pcie_clear_aggregators(pcie);
 
 	return IRQ_HANDLED;
 }
@@ -250,24 +442,47 @@ static void amd_mdb_pcie_free_irq_domains(struct amd_mdb_pcie *pcie)
 	}
 }
 
-static int amd_mdb_pcie_init_port(struct amd_mdb_pcie *pcie)
+static void amd_mdb_pcie_init_port(struct amd_mdb_pcie *pcie)
 {
-	unsigned long val;
+	u32 misc_mask_all;
+	u32 val;
+
+	misc_mask_all = pcie->variant->misc_mask_all;
 
 	/* Disable all TLP interrupts. */
-	writel_relaxed(AMD_MDB_PCIE_IMR_ALL_MASK,
-		       pcie->slcr + AMD_MDB_TLP_IR_DISABLE_MISC);
+	writel_relaxed(misc_mask_all,
+		       pcie->intr_base + pcie->variant->misc_disable_reg);
+
+	if (pcie->variant->version != MDB5)
+		writel_relaxed(AMD_CPM6_PCIE_ERR_MASK_ALL,
+			       pcie->intr_base + AMD_CPM6_PCIE_ERR_DISABLE);
 
 	/* Clear pending TLP interrupts. */
-	val = readl_relaxed(pcie->slcr + AMD_MDB_TLP_IR_STATUS_MISC);
-	val &= AMD_MDB_PCIE_IMR_ALL_MASK;
-	writel_relaxed(val, pcie->slcr + AMD_MDB_TLP_IR_STATUS_MISC);
+	val = readl_relaxed(pcie->intr_base + pcie->variant->misc_status_reg) &
+	      misc_mask_all;
+	writel_relaxed(val, pcie->intr_base + pcie->variant->misc_status_reg);
+
+	if (pcie->variant->version != MDB5) {
+		val = readl_relaxed(pcie->intr_base + AMD_CPM6_PCIE_ERR_STATUS) &
+		      AMD_CPM6_PCIE_ERR_MASK_ALL;
+		writel_relaxed(val, pcie->intr_base + AMD_CPM6_PCIE_ERR_STATUS);
+	}
 
 	/* Enable all TLP interrupts. */
-	writel_relaxed(AMD_MDB_PCIE_IMR_ALL_MASK,
-		       pcie->slcr + AMD_MDB_TLP_IR_ENABLE_MISC);
-
-	return 0;
+	writel_relaxed(misc_mask_all,
+		       pcie->intr_base + pcie->variant->misc_enable_reg);
+
+	if (pcie->variant->version != MDB5) {
+		writel_relaxed(AMD_CPM6_PCIE_ERR_MASK_ALL,
+			       pcie->intr_base + AMD_CPM6_PCIE_ERR_ENABLE);
+
+		/*
+		 * Unmask this host's MISC_EVENT and PCIE_ERR inputs in the
+		 * shared MERGED aggregator so they reach the GIC.
+		 */
+		writel_relaxed(amd_mdb_pcie_merged_host_mask(pcie),
+			       pcie->slcr + AMD_CPM6_MERGED_ENABLE);
+	}
 }
 
 /**
@@ -327,10 +542,13 @@ static int amd_mdb_pcie_init_irq_domains(struct amd_mdb_pcie *pcie,
 static irqreturn_t amd_mdb_pcie_intr_handler(int irq, void *args)
 {
 	struct amd_mdb_pcie *pcie = args;
+	const struct amd_mdb_intr_cause *intr_cause;
 	struct device *dev;
 	struct irq_data *d;
 
 	dev = pcie->pci.dev;
+	intr_cause = pcie->variant->version == MDB5 ?
+		     mdb5_intr_cause : cpm6_intr_cause;
 
 	/*
 	 * In the future, error reporting will be hooked to the AER subsystem.
@@ -351,15 +569,20 @@ static int amd_mdb_setup_irq(struct amd_mdb_pcie *pcie,
 	struct dw_pcie *pci = &pcie->pci;
 	struct dw_pcie_rp *pp = &pci->pp;
 	struct device *dev = &pdev->dev;
+	const struct amd_mdb_intr_cause *intr_cause;
+	unsigned long event_flags = IRQF_NO_THREAD;
 	int i, irq, err;
 
+	intr_cause = pcie->variant->version == MDB5 ?
+		     mdb5_intr_cause : cpm6_intr_cause;
+
 	amd_mdb_pcie_init_port(pcie);
 
 	pp->irq = platform_get_irq(pdev, 0);
 	if (pp->irq < 0)
 		return pp->irq;
 
-	for (i = 0; i < ARRAY_SIZE(intr_cause); i++) {
+	for (i = 0; i < ARRAY_SIZE(mdb5_intr_cause); i++) {
 		if (!intr_cause[i].str)
 			continue;
 
@@ -379,7 +602,7 @@ static int amd_mdb_setup_irq(struct amd_mdb_pcie *pcie,
 	}
 
 	pcie->intx_irq = irq_create_mapping(pcie->mdb_domain,
-					    AMD_MDB_PCIE_INTR_INTX);
+				    pcie->variant->intx_hwirq);
 	if (!pcie->intx_irq) {
 		dev_err(dev, "Failed to map INTx interrupt\n");
 		return -ENXIO;
@@ -393,8 +616,15 @@ static int amd_mdb_setup_irq(struct amd_mdb_pcie *pcie,
 		return err;
 	}
 
+	/*
+	 * On CPM6 the misc GIC line is shared between both host controllers,
+	 * so the event IRQ must allow sharing.
+	 */
+	if (pcie->variant->version != MDB5)
+		event_flags |= IRQF_SHARED;
+
 	/* Plug the main event handler. */
-	err = devm_request_irq(dev, pp->irq, amd_mdb_pcie_event, IRQF_NO_THREAD,
+	err = devm_request_irq(dev, pp->irq, amd_mdb_pcie_event, event_flags,
 			       "amd_mdb pcie_irq", pcie);
 	if (err) {
 		dev_err(dev, "Failed to request event IRQ %d, err=%d\n",
@@ -435,9 +665,36 @@ static int amd_mdb_add_pcie_port(struct amd_mdb_pcie *pcie,
 	struct device *dev = &pdev->dev;
 	int err;
 
-	pcie->slcr = devm_platform_ioremap_resource_byname(pdev, "slcr");
-	if (IS_ERR(pcie->slcr))
-		return PTR_ERR(pcie->slcr);
+	if (pcie->variant->version == MDB5) {
+		/*
+		 * On MDB5 all interrupt registers live in the SLCR block, so
+		 * the interrupt-register base simply aliases @slcr.
+		 */
+		pcie->slcr = devm_platform_ioremap_resource_byname(pdev, "slcr");
+		if (IS_ERR(pcie->slcr))
+			return PTR_ERR(pcie->slcr);
+		pcie->intr_base = pcie->slcr;
+	} else {
+		struct resource *res;
+
+		/*
+		 * CPM6 moves the per-controller MISC_EVENT/PCIE_ERR registers
+		 * into a separate "intr" region. The SLCR block, which holds
+		 * the shared MERGED/PS_MISC aggregators, is shared by both CPM6
+		 * host controllers, so map it without requesting exclusive
+		 * ownership; otherwise the second controller fails to probe.
+		 */
+		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "slcr");
+		if (!res)
+			return -EINVAL;
+		pcie->slcr = devm_ioremap(dev, res->start, resource_size(res));
+		if (!pcie->slcr)
+			return -ENOMEM;
+
+		pcie->intr_base = devm_platform_ioremap_resource_byname(pdev, "intr");
+		if (IS_ERR(pcie->intr_base))
+			return PTR_ERR(pcie->intr_base);
+	}
 
 	err = amd_mdb_pcie_init_irq_domains(pcie, pdev);
 	if (err)
@@ -483,6 +740,9 @@ static int amd_mdb_pcie_probe(struct platform_device *pdev)
 
 	pci = &pcie->pci;
 	pci->dev = dev;
+	pcie->variant = of_device_get_match_data(dev);
+	if (!pcie->variant)
+		return -EINVAL;
 
 	platform_set_drvdata(pdev, pcie);
 
@@ -514,9 +774,51 @@ static void amd_mdb_pcie_shutdown(struct platform_device *pdev)
 	gpiod_set_value_cansleep(pcie->perst_gpio, 1);
 }
 
+static const struct amd_mdb_pcie_variant cpm6_host = {
+	.version = CPM6,
+	.misc_status_reg = AMD_CPM6_MISC_EVENT_STATUS,
+	.misc_mask_reg = AMD_CPM6_MISC_EVENT_MASK,
+	.misc_enable_reg = AMD_CPM6_MISC_EVENT_ENABLE,
+	.misc_disable_reg = AMD_CPM6_MISC_EVENT_DISABLE,
+	.misc_mask_all = AMD_CPM6_MISC_EVENT_MASK_ALL,
+	.intx_hwirq = AMD_CPM6_PCIE_INTR_INTX,
+	.intx_mask = BIT(AMD_CPM6_PCIE_INTR_INTX),
+};
+
+static const struct amd_mdb_pcie_variant cpm6_host1 = {
+	.version = CPM6_HOST1,
+	.misc_status_reg = AMD_CPM6_MISC_EVENT_STATUS,
+	.misc_mask_reg = AMD_CPM6_MISC_EVENT_MASK,
+	.misc_enable_reg = AMD_CPM6_MISC_EVENT_ENABLE,
+	.misc_disable_reg = AMD_CPM6_MISC_EVENT_DISABLE,
+	.misc_mask_all = AMD_CPM6_MISC_EVENT_MASK_ALL,
+	.intx_hwirq = AMD_CPM6_PCIE_INTR_INTX,
+	.intx_mask = BIT(AMD_CPM6_PCIE_INTR_INTX),
+};
+
+static const struct amd_mdb_pcie_variant mdb5_host = {
+	.version = MDB5,
+	.misc_status_reg = AMD_MDB_TLP_IR_STATUS_MISC,
+	.misc_mask_reg = AMD_MDB_TLP_IR_MASK_MISC,
+	.misc_enable_reg = AMD_MDB_TLP_IR_ENABLE_MISC,
+	.misc_disable_reg = AMD_MDB_TLP_IR_DISABLE_MISC,
+	.misc_mask_all = AMD_MDB_PCIE_IMR_ALL_MASK,
+	.intx_hwirq = AMD_MDB_PCIE_INTR_INTX,
+	.intx_mask = AMD_MDB_TLP_PCIE_INTX_MASK,
+};
+
 static const struct of_device_id amd_mdb_pcie_of_match[] = {
 	{
 		.compatible = "amd,versal2-mdb-host",
+		.data = &mdb5_host,
+	},
+	{
+		.compatible = "amd,versal2-cpm6-host",
+		.data = &cpm6_host,
+	},
+	{
+		.compatible = "amd,versal2-cpm6-host1",
+		.data = &cpm6_host1,
 	},
 	{},
 };
-- 
2.44.4

Re: [PATCH v4 1/2] dt-bindings: PCI: amd-mdb: Add CPM6 support

[Rob Herring]

On Sat, Aug 08, 2026 at 04:22:55PM +0530, Sai Krishna Musham wrote:
> The AMD CPM6 PCIe controller is based on the Synopsys DesignWare PCIe IP.
> Add "intr" to snps,dw-pcie.yaml vendor-specific reg-names for the
> per-controller interrupt register region used by CPM6.
> 
> Update amd,versal2-mdb-host.yaml with separate register definitions:
> - MDB5: 4 regions (slcr, config, dbi, atu)
> - CPM6: 5 regions (slcr, config, dbi, atu, intr)
> 
> Signed-off-by: Sai Krishna Musham <sai.krishna.musham@amd.com>
> ---
> Changes in v4:
> - None
> 
> Changes in v3:
> - Update subject to match history.
> - Move allOf to the end, after required block.
> - Drop the CPM6 example.
> 
> Changes in v2:
> - Update the CPM6 device tree binding and example.
> 
> v1 https://lore.kernel.org/all/20260402180006.486229-2-sai.krishna.musham@amd.com/
> v2 https://lore.kernel.org/all/20260728202044.1785986-2-sai.krishna.musham@amd.com/
> v3 https://lore.kernel.org/all/20260803144412.713639-2-sai.krishna.musham@amd.com/
> ---
>  .../bindings/pci/amd,versal2-mdb-host.yaml    | 45 ++++++++++++++++---
>  .../devicetree/bindings/pci/snps,dw-pcie.yaml |  2 +
>  2 files changed, 42 insertions(+), 5 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml b/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml
> index 406c15e1dee1..672589066854 100644
> --- a/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml
> +++ b/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml
> @@ -9,27 +9,30 @@ title: AMD Versal2 MDB(Multimedia DMA Bridge) Host Controller
>  maintainers:
>    - Thippeswamy Havalige <thippeswamy.havalige@amd.com>
>  
> -allOf:
> -  - $ref: /schemas/pci/pci-host-bridge.yaml#
> -  - $ref: /schemas/pci/snps,dw-pcie.yaml#
> -
>  properties:
>    compatible:
> -    const: amd,versal2-mdb-host
> +    enum:
> +      - amd,versal2-mdb-host
> +      - amd,versal2-cpm6-host
> +      - amd,versal2-cpm6-host1

What is host and host1 difference? Please explain somewhere.

>  
>    reg:
> +    minItems: 4
>      items:
>        - description: MDB System Level Control and Status Register (SLCR) Base
>        - description: configuration region
>        - description: data bus interface
>        - description: address translation unit register
> +      - description: CPM6 PCIe error and event interrupt registers
>  
>    reg-names:
> +    minItems: 4
>      items:
>        - const: slcr
>        - const: config
>        - const: dbi
>        - const: atu
> +      - const: intr
>  
>    ranges:
>      maxItems: 2
> @@ -92,6 +95,38 @@ required:
>    - "#interrupt-cells"
>    - interrupt-controller
>  
> +allOf:
> +  - $ref: /schemas/pci/pci-host-bridge.yaml#
> +  - $ref: /schemas/pci/snps,dw-pcie.yaml#
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: amd,versal2-mdb-host
> +    then:
> +      properties:
> +        reg:
> +          minItems: 4

Drop. 4 is already the min.

> +          maxItems: 4
> +        reg-names:
> +          minItems: 4
> +          maxItems: 4
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - amd,versal2-cpm6-host
> +              - amd,versal2-cpm6-host1
> +    then:
> +      properties:
> +        reg:
> +          minItems: 5
> +          maxItems: 5

Drop. 5 is already the max.

> +        reg-names:
> +          minItems: 5
> +          maxItems: 5
> +
>  unevaluatedProperties: false
>  
>  examples:
> diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
> index b3216141881c..21f86609ddb6 100644
> --- a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
> +++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
> @@ -117,6 +117,8 @@ properties:
>                enum: [ ecam ]
>              - description: AMD MDB PCIe SLCR region
>                const: slcr
> +            - description: AMD CPM6 PCIe error and event interrupt registers
> +              const: intr
>      allOf:
>        - contains:
>            enum: [ dbi, ctrl ]
> -- 
> 2.44.4
>