[PATCH v3 0/4] irqchip: Add support for Aspeed AST2700 SCU interrupt controller

[PATCH v3 0/4] irqchip: Add support for Aspeed AST2700 SCU interrupt controller

[Ryan Chen]

This series adds support for the SCU (System Control Unit) interrupt
controllers on the Aspeed AST2700 SoC.

AST2700 follows the same multi-instance SCU interrupt controller design
as AST2600, with four independent interrupt domains (scu-ic0 to 3).
However, unlike previous SoCs that use a single register for both enable
and status bits, AST2700 splits them into separate IER (Interrupt Enable)
and ISR (Interrupt Status) registers.

To support this, the driver is refactored to use a variant-based init
structure, selected by compatible string. Register access is also
converted from regmap to MMIO (via `of_iomap()`), and a per-variant
IRQ handler is used depending on register layout.

v3:
- irq-aspeed-scu-ic.c
 - update for bracket-rules.
 - update TAB not spaces to align.
 - remove stray TAB.
 - update end up aligned.
 - add missing _ier, _isr in SCU_VARIANT.
 - add two different mask/unmask/ functions for split and combined.

v2:
- Refactor SCU IC driver to support variant-based initialization
- Add AST2700 compatible strings to YAML and header files
- Extend DT bindings in mfd and irqchip for AST2700
- Add IRQ handler logic for separate IER/ISR layout

Ryan Chen (4):
  irqchip/aspeed-scu-ic: Refactor driver to support variant-based
    initialization
  dt-bindings: mfd: aspeed: Add AST2700 SCU compatibles
  dt-bindings: interrupt-controller: aspeed: Add AST2700 SCU IC
    compatibles
  irqchip/aspeed-scu-ic: Add support AST2700 SCU interrupt controllers

 .../aspeed,ast2500-scu-ic.yaml                |   6 +-
 .../bindings/mfd/aspeed,ast2x00-scu.yaml      |   4 +
 drivers/irqchip/irq-aspeed-scu-ic.c           | 242 +++++++++++-------
 .../interrupt-controller/aspeed-scu-ic.h      |  14 +
 4 files changed, 173 insertions(+), 93 deletions(-)

-- 
2.34.1

[PATCH v3 1/4] irqchip/aspeed-scu-ic: Refactor driver to support variant-based initialization

[Ryan Chen]

The original SCU IC driver handled each AST2600 instance with separate
initialization functions and hardcoded register definitions. This patch
consolidates the implementation by introducing a variant-based structure,
selected via compatible string.

The driver now uses a unified init path and MMIO access via of_iomap().
This simplifies the code and prepares for upcoming SoCs like AST2700,
which require split register handling.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 drivers/irqchip/irq-aspeed-scu-ic.c | 143 ++++++++++++----------------
 1 file changed, 59 insertions(+), 84 deletions(-)

diff --git a/drivers/irqchip/irq-aspeed-scu-ic.c b/drivers/irqchip/irq-aspeed-scu-ic.c
index 1c7045467c48..24d3d3fa5c4b 100644
--- a/drivers/irqchip/irq-aspeed-scu-ic.c
+++ b/drivers/irqchip/irq-aspeed-scu-ic.c
@@ -7,52 +7,52 @@
  */
 
 #include <linux/bitops.h>
+#include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/irqchip.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
-#include <linux/mfd/syscon.h>
+#include <linux/of_address.h>
 #include <linux/of_irq.h>
-#include <linux/regmap.h>
 
-#define ASPEED_SCU_IC_REG		0x018
-#define ASPEED_SCU_IC_SHIFT		0
-#define ASPEED_SCU_IC_ENABLE		GENMASK(15, ASPEED_SCU_IC_SHIFT)
-#define ASPEED_SCU_IC_NUM_IRQS		7
 #define ASPEED_SCU_IC_STATUS		GENMASK(28, 16)
 #define ASPEED_SCU_IC_STATUS_SHIFT	16
 
-#define ASPEED_AST2600_SCU_IC0_REG	0x560
-#define ASPEED_AST2600_SCU_IC0_SHIFT	0
-#define ASPEED_AST2600_SCU_IC0_ENABLE	\
-	GENMASK(5, ASPEED_AST2600_SCU_IC0_SHIFT)
-#define ASPEED_AST2600_SCU_IC0_NUM_IRQS	6
+struct aspeed_scu_ic_variant {
+	const char		*compatible;
+	unsigned long	irq_enable;
+	unsigned long	irq_shift;
+	unsigned int	num_irqs;
+};
+
+#define SCU_VARIANT(_compat, _shift, _enable, _num) { \
+	.compatible		=	_compat,	\
+	.irq_shift		=	_shift,		\
+	.irq_enable		=	_enable,	\
+	.num_irqs		=	_num,		\
+}
 
-#define ASPEED_AST2600_SCU_IC1_REG	0x570
-#define ASPEED_AST2600_SCU_IC1_SHIFT	4
-#define ASPEED_AST2600_SCU_IC1_ENABLE	\
-	GENMASK(5, ASPEED_AST2600_SCU_IC1_SHIFT)
-#define ASPEED_AST2600_SCU_IC1_NUM_IRQS	2
+static const struct aspeed_scu_ic_variant scu_ic_variants[]	__initconst = {
+	SCU_VARIANT("aspeed,ast2400-scu-ic",	0,	GENMASK(15, 0),	7),
+	SCU_VARIANT("aspeed,ast2500-scu-ic",	0,	GENMASK(15, 0), 7),
+	SCU_VARIANT("aspeed,ast2600-scu-ic0",	0,	GENMASK(5, 0),	6),
+	SCU_VARIANT("aspeed,ast2600-scu-ic1",	4,	GENMASK(5, 4),	2),
+};
 
 struct aspeed_scu_ic {
-	unsigned long irq_enable;
-	unsigned long irq_shift;
-	unsigned int num_irqs;
-	unsigned int reg;
-	struct regmap *scu;
-	struct irq_domain *irq_domain;
+	unsigned long		irq_enable;
+	unsigned long		irq_shift;
+	unsigned int		num_irqs;
+	void __iomem		*base;
+	struct irq_domain	*irq_domain;
 };
 
 static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
 {
-	unsigned int sts;
-	unsigned long bit;
-	unsigned long enabled;
-	unsigned long max;
-	unsigned long status;
 	struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-	unsigned int mask = scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT;
+	unsigned long bit, enabled, max, status;
+	unsigned int sts, mask;
 
 	chained_irq_enter(chip, desc);
 
@@ -66,7 +66,7 @@ static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
 	 * shifting the status down to get the mapping and then back up to
 	 * clear the bit.
 	 */
-	regmap_read(scu_ic->scu, scu_ic->reg, &sts);
+	sts = readl(scu_ic->base);
 	enabled = sts & scu_ic->irq_enable;
 	status = (sts >> ASPEED_SCU_IC_STATUS_SHIFT) & enabled;
 
@@ -76,9 +76,9 @@ static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
 	for_each_set_bit_from(bit, &status, max) {
 		generic_handle_domain_irq(scu_ic->irq_domain,
 					  bit - scu_ic->irq_shift);
-
-		regmap_write_bits(scu_ic->scu, scu_ic->reg, mask,
-				  BIT(bit + ASPEED_SCU_IC_STATUS_SHIFT));
+		writel((readl(scu_ic->base) & ~mask) |
+		       BIT(bit + ASPEED_SCU_IC_STATUS_SHIFT),
+		       scu_ic->base);
 	}
 
 	chained_irq_exit(chip, desc);
@@ -95,7 +95,7 @@ static void aspeed_scu_ic_irq_mask(struct irq_data *data)
 	 * operation from clearing the status bits, they should be under the
 	 * mask and written with 0.
 	 */
-	regmap_update_bits(scu_ic->scu, scu_ic->reg, mask, 0);
+	writel(readl(scu_ic->base) & ~mask, scu_ic->base);
 }
 
 static void aspeed_scu_ic_irq_unmask(struct irq_data *data)
@@ -110,7 +110,7 @@ static void aspeed_scu_ic_irq_unmask(struct irq_data *data)
 	 * operation from clearing the status bits, they should be under the
 	 * mask and written with 0.
 	 */
-	regmap_update_bits(scu_ic->scu, scu_ic->reg, mask, bit);
+	writel((readl(scu_ic->base) & ~mask) | bit, scu_ic->base);
 }
 
 static int aspeed_scu_ic_irq_set_affinity(struct irq_data *data,
@@ -146,18 +146,13 @@ static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic,
 	int irq;
 	int rc = 0;
 
-	if (!node->parent) {
-		rc = -ENODEV;
+	scu_ic->base = of_iomap(node, 0);
+	if (IS_ERR(scu_ic->base)) {
+		rc = PTR_ERR(scu_ic->base);
 		goto err;
 	}
-
-	scu_ic->scu = syscon_node_to_regmap(node->parent);
-	if (IS_ERR(scu_ic->scu)) {
-		rc = PTR_ERR(scu_ic->scu);
-		goto err;
-	}
-	regmap_write_bits(scu_ic->scu, scu_ic->reg, ASPEED_SCU_IC_STATUS, ASPEED_SCU_IC_STATUS);
-	regmap_write_bits(scu_ic->scu, scu_ic->reg, ASPEED_SCU_IC_ENABLE, 0);
+	writel(ASPEED_SCU_IC_STATUS, scu_ic->base);
+	writel(0, scu_ic->base);
 
 	irq = irq_of_parse_and_map(node, 0);
 	if (!irq) {
@@ -166,8 +161,7 @@ static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic,
 	}
 
 	scu_ic->irq_domain = irq_domain_create_linear(of_fwnode_handle(node), scu_ic->num_irqs,
-						   &aspeed_scu_ic_domain_ops,
-						   scu_ic);
+						      &aspeed_scu_ic_domain_ops, scu_ic);
 	if (!scu_ic->irq_domain) {
 		rc = -ENOMEM;
 		goto err;
@@ -184,57 +178,38 @@ static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic,
 	return rc;
 }
 
-static int __init aspeed_scu_ic_of_init(struct device_node *node,
-					struct device_node *parent)
+static const struct aspeed_scu_ic_variant *
+aspeed_scu_ic_find_variant(struct device_node *np)
 {
-	struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
-
-	if (!scu_ic)
-		return -ENOMEM;
-
-	scu_ic->irq_enable = ASPEED_SCU_IC_ENABLE;
-	scu_ic->irq_shift = ASPEED_SCU_IC_SHIFT;
-	scu_ic->num_irqs = ASPEED_SCU_IC_NUM_IRQS;
-	scu_ic->reg = ASPEED_SCU_IC_REG;
+	for (int i = 0; i < ARRAY_SIZE(scu_ic_variants); i++) {
+		if (of_device_is_compatible(np, scu_ic_variants[i].compatible))
+			return &scu_ic_variants[i];
+	}
 
-	return aspeed_scu_ic_of_init_common(scu_ic, node);
+	return NULL;
 }
 
-static int __init aspeed_ast2600_scu_ic0_of_init(struct device_node *node,
-						 struct device_node *parent)
+static int __init aspeed_scu_ic_of_init(struct device_node *node, struct device_node *parent)
 {
-	struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
-
-	if (!scu_ic)
-		return -ENOMEM;
+	const struct aspeed_scu_ic_variant *variant;
+	struct aspeed_scu_ic *scu_ic;
 
-	scu_ic->irq_enable = ASPEED_AST2600_SCU_IC0_ENABLE;
-	scu_ic->irq_shift = ASPEED_AST2600_SCU_IC0_SHIFT;
-	scu_ic->num_irqs = ASPEED_AST2600_SCU_IC0_NUM_IRQS;
-	scu_ic->reg = ASPEED_AST2600_SCU_IC0_REG;
-
-	return aspeed_scu_ic_of_init_common(scu_ic, node);
-}
-
-static int __init aspeed_ast2600_scu_ic1_of_init(struct device_node *node,
-						 struct device_node *parent)
-{
-	struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
+	variant = aspeed_scu_ic_find_variant(node);
+	if (!variant)
+		return -ENODEV;
 
+	scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
 	if (!scu_ic)
 		return -ENOMEM;
 
-	scu_ic->irq_enable = ASPEED_AST2600_SCU_IC1_ENABLE;
-	scu_ic->irq_shift = ASPEED_AST2600_SCU_IC1_SHIFT;
-	scu_ic->num_irqs = ASPEED_AST2600_SCU_IC1_NUM_IRQS;
-	scu_ic->reg = ASPEED_AST2600_SCU_IC1_REG;
+	scu_ic->irq_enable	= variant->irq_enable;
+	scu_ic->irq_shift	= variant->irq_shift;
+	scu_ic->num_irqs	= variant->num_irqs;
 
 	return aspeed_scu_ic_of_init_common(scu_ic, node);
 }
 
 IRQCHIP_DECLARE(ast2400_scu_ic, "aspeed,ast2400-scu-ic", aspeed_scu_ic_of_init);
 IRQCHIP_DECLARE(ast2500_scu_ic, "aspeed,ast2500-scu-ic", aspeed_scu_ic_of_init);
-IRQCHIP_DECLARE(ast2600_scu_ic0, "aspeed,ast2600-scu-ic0",
-		aspeed_ast2600_scu_ic0_of_init);
-IRQCHIP_DECLARE(ast2600_scu_ic1, "aspeed,ast2600-scu-ic1",
-		aspeed_ast2600_scu_ic1_of_init);
+IRQCHIP_DECLARE(ast2600_scu_ic0, "aspeed,ast2600-scu-ic0", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2600_scu_ic1, "aspeed,ast2600-scu-ic1", aspeed_scu_ic_of_init);
-- 
2.34.1

Re: [PATCH v3 1/4] irqchip/aspeed-scu-ic: Refactor driver to support variant-based initialization

[kernel test robot]

Hi Ryan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on tip/irq/core]
[also build test WARNING on robh/for-next lee-mfd/for-mfd-next lee-mfd/for-mfd-fixes linus/master v6.17-rc4 next-20250905]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ryan-Chen/irqchip-aspeed-scu-ic-Refactor-driver-to-support-variant-based-initialization/20250906-095043
base:   tip/irq/core
patch link:    https://lore.kernel.org/r/20250906014846.861368-2-ryan_chen%40aspeedtech.com
patch subject: [PATCH v3 1/4] irqchip/aspeed-scu-ic: Refactor driver to support variant-based initialization
config: arm-randconfig-001-20250906 (https://download.01.org/0day-ci/archive/20250907/202509070058.3Z4AtICl-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 7fb1dc08d2f025aad5777bb779dfac1197e9ef87)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250907/202509070058.3Z4AtICl-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509070058.3Z4AtICl-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/irqchip/irq-aspeed-scu-ic.c:79:34: warning: variable 'mask' is uninitialized when used here [-Wuninitialized]
      79 |                 writel((readl(scu_ic->base) & ~mask) |
         |                                                ^~~~
   drivers/irqchip/irq-aspeed-scu-ic.c:55:24: note: initialize the variable 'mask' to silence this warning
      55 |         unsigned int sts, mask;
         |                               ^
         |                                = 0
   1 warning generated.


vim +/mask +79 drivers/irqchip/irq-aspeed-scu-ic.c

    49	
    50	static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
    51	{
    52		struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc);
    53		struct irq_chip *chip = irq_desc_get_chip(desc);
    54		unsigned long bit, enabled, max, status;
    55		unsigned int sts, mask;
    56	
    57		chained_irq_enter(chip, desc);
    58	
    59		/*
    60		 * The SCU IC has just one register to control its operation and read
    61		 * status. The interrupt enable bits occupy the lower 16 bits of the
    62		 * register, while the interrupt status bits occupy the upper 16 bits.
    63		 * The status bit for a given interrupt is always 16 bits shifted from
    64		 * the enable bit for the same interrupt.
    65		 * Therefore, perform the IRQ operations in the enable bit space by
    66		 * shifting the status down to get the mapping and then back up to
    67		 * clear the bit.
    68		 */
    69		sts = readl(scu_ic->base);
    70		enabled = sts & scu_ic->irq_enable;
    71		status = (sts >> ASPEED_SCU_IC_STATUS_SHIFT) & enabled;
    72	
    73		bit = scu_ic->irq_shift;
    74		max = scu_ic->num_irqs + bit;
    75	
    76		for_each_set_bit_from(bit, &status, max) {
    77			generic_handle_domain_irq(scu_ic->irq_domain,
    78						  bit - scu_ic->irq_shift);
  > 79			writel((readl(scu_ic->base) & ~mask) |
    80			       BIT(bit + ASPEED_SCU_IC_STATUS_SHIFT),
    81			       scu_ic->base);
    82		}
    83	
    84		chained_irq_exit(chip, desc);
    85	}
    86	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

[PATCH v3 2/4] dt-bindings: mfd: aspeed: Add AST2700 SCU compatibles

[Ryan Chen]

Add SCU interrupt controller compatible strings for the AST2700 SoC:
scu-ic0 to 3. This extends the MFD binding to support AST2700-based
platforms.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
---
 Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml b/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
index 5eccd10d95ce..67be6d095fe4 100644
--- a/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
+++ b/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
@@ -75,6 +75,10 @@ patternProperties:
             - aspeed,ast2500-scu-ic
             - aspeed,ast2600-scu-ic0
             - aspeed,ast2600-scu-ic1
+            - aspeed,ast2700-scu-ic0
+            - aspeed,ast2700-scu-ic1
+            - aspeed,ast2700-scu-ic2
+            - aspeed,ast2700-scu-ic3
 
   '^silicon-id@[0-9a-f]+$':
     description: Unique hardware silicon identifiers within the SoC
-- 
2.34.1

[PATCH v3 3/4] dt-bindings: interrupt-controller: aspeed: Add AST2700 SCU IC compatibles

[Ryan Chen]

Add compatible strings for the four SCU interrupt controller instances
on the AST2700 SoC (scu-ic0 to 3), following the multi-instance model used
on AST2600.

Also define interrupt indices in the binding header.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
---
 .../aspeed,ast2500-scu-ic.yaml                     |  6 +++++-
 .../interrupt-controller/aspeed-scu-ic.h           | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2500-scu-ic.yaml b/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2500-scu-ic.yaml
index d5287a2bf866..d998a9d69b91 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2500-scu-ic.yaml
+++ b/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2500-scu-ic.yaml
@@ -5,7 +5,7 @@
 $id: http://devicetree.org/schemas/interrupt-controller/aspeed,ast2500-scu-ic.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: Aspeed AST25XX and AST26XX SCU Interrupt Controller
+title: Aspeed AST25XX, AST26XX, AST27XX SCU Interrupt Controller
 
 maintainers:
   - Eddie James <eajames@linux.ibm.com>
@@ -16,6 +16,10 @@ properties:
       - aspeed,ast2500-scu-ic
       - aspeed,ast2600-scu-ic0
       - aspeed,ast2600-scu-ic1
+      - aspeed,ast2700-scu-ic0
+      - aspeed,ast2700-scu-ic1
+      - aspeed,ast2700-scu-ic2
+      - aspeed,ast2700-scu-ic3
 
   reg:
     maxItems: 1
diff --git a/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h b/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
index f315d5a7f5ee..7dd04424afcc 100644
--- a/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
+++ b/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
@@ -20,4 +20,18 @@
 #define ASPEED_AST2600_SCU_IC1_LPC_RESET_LO_TO_HI	0
 #define ASPEED_AST2600_SCU_IC1_LPC_RESET_HI_TO_LO	1
 
+#define ASPEED_AST2700_SCU_IC0_PCIE_PERST_LO_TO_HI	3
+#define ASPEED_AST2700_SCU_IC0_PCIE_PERST_HI_TO_LO	2
+
+#define ASPEED_AST2700_SCU_IC1_PCIE_RCRST_LO_TO_HI	3
+#define ASPEED_AST2700_SCU_IC1_PCIE_RCRST_HI_TO_LO	2
+
+#define ASPEED_AST2700_SCU_IC2_PCIE_PERST_LO_TO_HI	3
+#define ASPEED_AST2700_SCU_IC2_PCIE_PERST_HI_TO_LO	2
+#define ASPEED_AST2700_SCU_IC2_LPC_RESET_LO_TO_HI	1
+#define ASPEED_AST2700_SCU_IC2_LPC_RESET_HI_TO_LO	0
+
+#define ASPEED_AST2700_SCU_IC3_LPC_RESET_LO_TO_HI	1
+#define ASPEED_AST2700_SCU_IC3_LPC_RESET_HI_TO_LO	0
+
 #endif /* _DT_BINDINGS_INTERRUPT_CONTROLLER_ASPEED_SCU_IC_H_ */
-- 
2.34.1

[PATCH v3 4/4] irqchip/aspeed-scu-ic: Add support AST2700 SCU interrupt controllers

[Ryan Chen]

The AST2700 continues the multi-instance SCU interrupt controller model
introduced in the AST2600, with four independent interrupt domains
(scu-ic0 to 3).

Unlike earlier generations that combine interrupt enable and status bits
into a single register, the AST2700 separates these into distinct IER and
ISR registers. Support for this layout is implemented by using register
offsets and separate chained IRQ handlers.

The variant table is extended to cover AST2700 IC instances, enabling
shared initialization logic while preserving support for previous SoCs.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 drivers/irqchip/irq-aspeed-scu-ic.c | 119 +++++++++++++++++++++++-----
 1 file changed, 101 insertions(+), 18 deletions(-)

diff --git a/drivers/irqchip/irq-aspeed-scu-ic.c b/drivers/irqchip/irq-aspeed-scu-ic.c
index 24d3d3fa5c4b..8c2df72353be 100644
--- a/drivers/irqchip/irq-aspeed-scu-ic.c
+++ b/drivers/irqchip/irq-aspeed-scu-ic.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
- * Aspeed AST24XX, AST25XX, and AST26XX SCU Interrupt Controller
+ * Aspeed AST24XX, AST25XX, AST26XX, and AST27XX SCU Interrupt Controller
  * Copyright 2019 IBM Corporation
  *
  * Eddie James <eajames@linux.ibm.com>
@@ -17,26 +17,37 @@
 
 #define ASPEED_SCU_IC_STATUS		GENMASK(28, 16)
 #define ASPEED_SCU_IC_STATUS_SHIFT	16
+#define AST2700_SCU_IC_STATUS		GENMASK(15, 0)
 
 struct aspeed_scu_ic_variant {
 	const char		*compatible;
 	unsigned long	irq_enable;
 	unsigned long	irq_shift;
 	unsigned int	num_irqs;
+	bool		split_ier_isr;
+	unsigned long	ier;
+	unsigned long	isr;
 };
 
-#define SCU_VARIANT(_compat, _shift, _enable, _num) { \
+#define SCU_VARIANT(_compat, _shift, _enable, _num, _split, _ier, _isr) { \
 	.compatible		=	_compat,	\
 	.irq_shift		=	_shift,		\
 	.irq_enable		=	_enable,	\
 	.num_irqs		=	_num,		\
+	.split_ier_isr		=	_split,		\
+	.ier			=	_ier,		\
+	.isr			=	_isr,		\
 }
 
 static const struct aspeed_scu_ic_variant scu_ic_variants[]	__initconst = {
-	SCU_VARIANT("aspeed,ast2400-scu-ic",	0,	GENMASK(15, 0),	7),
-	SCU_VARIANT("aspeed,ast2500-scu-ic",	0,	GENMASK(15, 0), 7),
-	SCU_VARIANT("aspeed,ast2600-scu-ic0",	0,	GENMASK(5, 0),	6),
-	SCU_VARIANT("aspeed,ast2600-scu-ic1",	4,	GENMASK(5, 4),	2),
+	SCU_VARIANT("aspeed,ast2400-scu-ic",	0, GENMASK(15, 0),	7, false,	0,	0),
+	SCU_VARIANT("aspeed,ast2500-scu-ic",	0, GENMASK(15, 0),	7, false,	0,	0),
+	SCU_VARIANT("aspeed,ast2600-scu-ic0",	0, GENMASK(5, 0),	6, false,	0,	0),
+	SCU_VARIANT("aspeed,ast2600-scu-ic1",	4, GENMASK(5, 4),	2, false,	0,	0),
+	SCU_VARIANT("aspeed,ast2700-scu-ic0",	0, GENMASK(3, 0),	4, true,	0x00, 0x04),
+	SCU_VARIANT("aspeed,ast2700-scu-ic1",	0, GENMASK(3, 0),	4, true,	0x00, 0x04),
+	SCU_VARIANT("aspeed,ast2700-scu-ic2",	0, GENMASK(3, 0),	4, true,	0x04, 0x00),
+	SCU_VARIANT("aspeed,ast2700-scu-ic3",	0, GENMASK(1, 0),	2, true,	0x04, 0x00),
 };
 
 struct aspeed_scu_ic {
@@ -45,9 +56,12 @@ struct aspeed_scu_ic {
 	unsigned int		num_irqs;
 	void __iomem		*base;
 	struct irq_domain	*irq_domain;
+	bool			split_ier_isr;
+	unsigned long		ier;
+	unsigned long		isr;
 };
 
-static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
+static void aspeed_scu_ic_irq_handler_combined(struct irq_desc *desc)
 {
 	struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
@@ -84,7 +98,33 @@ static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
 	chained_irq_exit(chip, desc);
 }
 
-static void aspeed_scu_ic_irq_mask(struct irq_data *data)
+static void aspeed_scu_ic_irq_handler_split(struct irq_desc *desc)
+{
+	struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	unsigned long bit, enabled, max, status;
+	unsigned int sts, mask;
+
+	chained_irq_enter(chip, desc);
+
+	mask = scu_ic->irq_enable;
+	sts = readl(scu_ic->base + scu_ic->isr);
+	enabled = sts & scu_ic->irq_enable;
+	sts = readl(scu_ic->base + scu_ic->isr);
+	status = sts & enabled;
+
+	bit = scu_ic->irq_shift;
+	max = scu_ic->num_irqs + bit;
+
+	for_each_set_bit_from(bit, &status, max) {
+		generic_handle_domain_irq(scu_ic->irq_domain, bit - scu_ic->irq_shift);
+		writel(BIT(bit), scu_ic->base + scu_ic->isr); // clear interrupt
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static void aspeed_scu_ic_irq_mask_combined(struct irq_data *data)
 {
 	struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data);
 	unsigned int mask = BIT(data->hwirq + scu_ic->irq_shift) |
@@ -98,7 +138,7 @@ static void aspeed_scu_ic_irq_mask(struct irq_data *data)
 	writel(readl(scu_ic->base) & ~mask, scu_ic->base);
 }
 
-static void aspeed_scu_ic_irq_unmask(struct irq_data *data)
+static void aspeed_scu_ic_irq_unmask_combined(struct irq_data *data)
 {
 	struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data);
 	unsigned int bit = BIT(data->hwirq + scu_ic->irq_shift);
@@ -113,6 +153,22 @@ static void aspeed_scu_ic_irq_unmask(struct irq_data *data)
 	writel((readl(scu_ic->base) & ~mask) | bit, scu_ic->base);
 }
 
+static void aspeed_scu_ic_irq_mask_split(struct irq_data *data)
+{
+	struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data);
+
+	writel(readl(scu_ic->base) & ~BIT(data->hwirq + scu_ic->irq_shift),
+	       scu_ic->base + scu_ic->ier);
+}
+
+static void aspeed_scu_ic_irq_unmask_split(struct irq_data *data)
+{
+	struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data);
+	unsigned int bit = BIT(data->hwirq + scu_ic->irq_shift);
+
+	writel(readl(scu_ic->base) | bit, scu_ic->base + scu_ic->ier);
+}
+
 static int aspeed_scu_ic_irq_set_affinity(struct irq_data *data,
 					  const struct cpumask *dest,
 					  bool force)
@@ -120,17 +176,29 @@ static int aspeed_scu_ic_irq_set_affinity(struct irq_data *data,
 	return -EINVAL;
 }
 
-static struct irq_chip aspeed_scu_ic_chip = {
-	.name			= "aspeed-scu-ic",
-	.irq_mask		= aspeed_scu_ic_irq_mask,
-	.irq_unmask		= aspeed_scu_ic_irq_unmask,
-	.irq_set_affinity	= aspeed_scu_ic_irq_set_affinity,
+static struct irq_chip aspeed_scu_ic_chip_combined = {
+	.name                   = "aspeed-scu-ic",
+	.irq_mask               = aspeed_scu_ic_irq_mask_combined,
+	.irq_unmask             = aspeed_scu_ic_irq_unmask_combined,
+	.irq_set_affinity       = aspeed_scu_ic_irq_set_affinity,
+};
+
+static struct irq_chip aspeed_scu_ic_chip_split = {
+	.name                   = "ast2700-scu-ic",
+	.irq_mask               = aspeed_scu_ic_irq_mask_split,
+	.irq_unmask             = aspeed_scu_ic_irq_unmask_split,
+	.irq_set_affinity       = aspeed_scu_ic_irq_set_affinity,
 };
 
 static int aspeed_scu_ic_map(struct irq_domain *domain, unsigned int irq,
 			     irq_hw_number_t hwirq)
 {
-	irq_set_chip_and_handler(irq, &aspeed_scu_ic_chip, handle_level_irq);
+	struct aspeed_scu_ic *scu_ic = domain->host_data;
+
+	if (scu_ic->split_ier_isr)
+		irq_set_chip_and_handler(irq, &aspeed_scu_ic_chip_split, handle_level_irq);
+	else
+		irq_set_chip_and_handler(irq, &aspeed_scu_ic_chip_combined, handle_level_irq);
 	irq_set_chip_data(irq, domain->host_data);
 
 	return 0;
@@ -151,8 +219,14 @@ static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic,
 		rc = PTR_ERR(scu_ic->base);
 		goto err;
 	}
-	writel(ASPEED_SCU_IC_STATUS, scu_ic->base);
-	writel(0, scu_ic->base);
+
+	if (scu_ic->split_ier_isr) {
+		writel(AST2700_SCU_IC_STATUS, scu_ic->base + scu_ic->isr);
+		writel(0, scu_ic->base + scu_ic->ier);
+	} else {
+		writel(ASPEED_SCU_IC_STATUS, scu_ic->base);
+		writel(0, scu_ic->base);
+	}
 
 	irq = irq_of_parse_and_map(node, 0);
 	if (!irq) {
@@ -167,7 +241,9 @@ static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic,
 		goto err;
 	}
 
-	irq_set_chained_handler_and_data(irq, aspeed_scu_ic_irq_handler,
+	irq_set_chained_handler_and_data(irq, scu_ic->split_ier_isr ?
+					 aspeed_scu_ic_irq_handler_split :
+					 aspeed_scu_ic_irq_handler_combined,
 					 scu_ic);
 
 	return 0;
@@ -205,6 +281,9 @@ static int __init aspeed_scu_ic_of_init(struct device_node *node, struct device_
 	scu_ic->irq_enable	= variant->irq_enable;
 	scu_ic->irq_shift	= variant->irq_shift;
 	scu_ic->num_irqs	= variant->num_irqs;
+	scu_ic->split_ier_isr	= variant->split_ier_isr;
+	scu_ic->ier	= variant->ier;
+	scu_ic->isr	= variant->isr;
 
 	return aspeed_scu_ic_of_init_common(scu_ic, node);
 }
@@ -213,3 +292,7 @@ IRQCHIP_DECLARE(ast2400_scu_ic, "aspeed,ast2400-scu-ic", aspeed_scu_ic_of_init);
 IRQCHIP_DECLARE(ast2500_scu_ic, "aspeed,ast2500-scu-ic", aspeed_scu_ic_of_init);
 IRQCHIP_DECLARE(ast2600_scu_ic0, "aspeed,ast2600-scu-ic0", aspeed_scu_ic_of_init);
 IRQCHIP_DECLARE(ast2600_scu_ic1, "aspeed,ast2600-scu-ic1", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2700_scu_ic0, "aspeed,ast2700-scu-ic0", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2700_scu_ic1, "aspeed,ast2700-scu-ic1", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2700_scu_ic2, "aspeed,ast2700-scu-ic2", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2700_scu_ic3, "aspeed,ast2700-scu-ic3", aspeed_scu_ic_of_init);
-- 
2.34.1

Re: [PATCH v3 4/4] irqchip/aspeed-scu-ic: Add support AST2700 SCU interrupt controllers

[kernel test robot]

Hi Ryan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on tip/irq/core]
[also build test WARNING on robh/for-next lee-mfd/for-mfd-next lee-mfd/for-mfd-fixes linus/master v6.17-rc4 next-20250905]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ryan-Chen/irqchip-aspeed-scu-ic-Refactor-driver-to-support-variant-based-initialization/20250906-095043
base:   tip/irq/core
patch link:    https://lore.kernel.org/r/20250906014846.861368-5-ryan_chen%40aspeedtech.com
patch subject: [PATCH v3 4/4] irqchip/aspeed-scu-ic: Add support AST2700 SCU interrupt controllers
config: arm-randconfig-001-20250906 (https://download.01.org/0day-ci/archive/20250907/202509070538.5HcCJf2T-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 7fb1dc08d2f025aad5777bb779dfac1197e9ef87)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250907/202509070538.5HcCJf2T-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509070538.5HcCJf2T-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/irqchip/irq-aspeed-scu-ic.c:93:34: warning: variable 'mask' is uninitialized when used here [-Wuninitialized]
      93 |                 writel((readl(scu_ic->base) & ~mask) |
         |                                                ^~~~
   drivers/irqchip/irq-aspeed-scu-ic.c:69:24: note: initialize the variable 'mask' to silence this warning
      69 |         unsigned int sts, mask;
         |                               ^
         |                                = 0
>> drivers/irqchip/irq-aspeed-scu-ic.c:106:20: warning: variable 'mask' set but not used [-Wunused-but-set-variable]
     106 |         unsigned int sts, mask;
         |                           ^
   2 warnings generated.


vim +/mask +106 drivers/irqchip/irq-aspeed-scu-ic.c

   100	
   101	static void aspeed_scu_ic_irq_handler_split(struct irq_desc *desc)
   102	{
   103		struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc);
   104		struct irq_chip *chip = irq_desc_get_chip(desc);
   105		unsigned long bit, enabled, max, status;
 > 106		unsigned int sts, mask;
   107	
   108		chained_irq_enter(chip, desc);
   109	
   110		mask = scu_ic->irq_enable;
   111		sts = readl(scu_ic->base + scu_ic->isr);
   112		enabled = sts & scu_ic->irq_enable;
   113		sts = readl(scu_ic->base + scu_ic->isr);
   114		status = sts & enabled;
   115	
   116		bit = scu_ic->irq_shift;
   117		max = scu_ic->num_irqs + bit;
   118	
   119		for_each_set_bit_from(bit, &status, max) {
   120			generic_handle_domain_irq(scu_ic->irq_domain, bit - scu_ic->irq_shift);
   121			writel(BIT(bit), scu_ic->base + scu_ic->isr); // clear interrupt
   122		}
   123	
   124		chained_irq_exit(chip, desc);
   125	}
   126	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki