diff mbox series

[v2,3/9] irqchip/riscv-intc: Add support for RISC-V AIA

Message ID 20230103141409.772298-4-apatel@ventanamicro.com
State New
Headers show
Series [v2,1/9] RISC-V: Add AIA related CSR defines | expand

Commit Message

Anup Patel Jan. 3, 2023, 2:14 p.m. UTC
The RISC-V advanced interrupt architecture (AIA) extends the per-HART
local interrupts in following ways:
1. Minimum 64 local interrupts for both RV32 and RV64
2. Ability to process multiple pending local interrupts in same
   interrupt handler
3. Priority configuration for each local interrupts
4. Special CSRs to configure/access the per-HART MSI controller

This patch adds support for RISC-V AIA in the RISC-V intc driver.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 drivers/irqchip/irq-riscv-intc.c | 37 ++++++++++++++++++++++++++------
 1 file changed, 31 insertions(+), 6 deletions(-)

Comments

Marc Zyngier Jan. 13, 2023, 9:39 a.m. UTC | #1
On Tue, 03 Jan 2023 14:14:03 +0000,
Anup Patel <apatel@ventanamicro.com> wrote:
> 
> The RISC-V advanced interrupt architecture (AIA) extends the per-HART
> local interrupts in following ways:
> 1. Minimum 64 local interrupts for both RV32 and RV64
> 2. Ability to process multiple pending local interrupts in same
>    interrupt handler
> 3. Priority configuration for each local interrupts
> 4. Special CSRs to configure/access the per-HART MSI controller
> 
> This patch adds support for RISC-V AIA in the RISC-V intc driver.
> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
>  drivers/irqchip/irq-riscv-intc.c | 37 ++++++++++++++++++++++++++------
>  1 file changed, 31 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
> index f229e3e66387..880d1639aadc 100644
> --- a/drivers/irqchip/irq-riscv-intc.c
> +++ b/drivers/irqchip/irq-riscv-intc.c
> @@ -16,6 +16,7 @@
>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/smp.h>
> +#include <asm/hwcap.h>
>  
>  static struct irq_domain *intc_domain;
>  
> @@ -29,6 +30,15 @@ static asmlinkage void riscv_intc_irq(struct pt_regs *regs)
>  	generic_handle_domain_irq(intc_domain, cause);
>  }
>  
> +static asmlinkage void riscv_intc_aia_irq(struct pt_regs *regs)

What does "static asmlinkage" in a C file even mean? And clearly, this
isn't the only instance in this file...

> +{
> +	unsigned long topi;
> +
> +	while ((topi = csr_read(CSR_TOPI)))
> +		generic_handle_domain_irq(intc_domain,
> +					  topi >> TOPI_IID_SHIFT);
> +}
> +
>  /*
>   * On RISC-V systems local interrupts are masked or unmasked by writing
>   * the SIE (Supervisor Interrupt Enable) CSR.  As CSRs can only be written
> @@ -38,12 +48,18 @@ static asmlinkage void riscv_intc_irq(struct pt_regs *regs)
>  
>  static void riscv_intc_irq_mask(struct irq_data *d)
>  {
> -	csr_clear(CSR_IE, BIT(d->hwirq));
> +	if (d->hwirq < BITS_PER_LONG)

And what if BIT_PER_LONG is 32, as I expect it to be on 32bit, which
the commit message says is supported?

> +		csr_clear(CSR_IE, BIT(d->hwirq));
> +	else
> +		csr_clear(CSR_IEH, BIT(d->hwirq - BITS_PER_LONG));
>  }
>  
>  static void riscv_intc_irq_unmask(struct irq_data *d)
>  {
> -	csr_set(CSR_IE, BIT(d->hwirq));
> +	if (d->hwirq < BITS_PER_LONG)
> +		csr_set(CSR_IE, BIT(d->hwirq));
> +	else
> +		csr_set(CSR_IEH, BIT(d->hwirq - BITS_PER_LONG));
>  }
>  
>  static void riscv_intc_irq_eoi(struct irq_data *d)
> @@ -115,7 +131,7 @@ static struct fwnode_handle *riscv_intc_hwnode(void)
>  static int __init riscv_intc_init(struct device_node *node,
>  				  struct device_node *parent)
>  {
> -	int rc;
> +	int rc, nr_irqs;
>  	unsigned long hartid;
>  
>  	rc = riscv_of_parent_hartid(node, &hartid);
> @@ -133,14 +149,21 @@ static int __init riscv_intc_init(struct device_node *node,
>  	if (riscv_hartid_to_cpuid(hartid) != smp_processor_id())
>  		return 0;
>  
> -	intc_domain = irq_domain_add_linear(node, BITS_PER_LONG,
> +	nr_irqs = BITS_PER_LONG;
> +	if (riscv_isa_extension_available(NULL, SxAIA) && BITS_PER_LONG == 32)
> +		nr_irqs = nr_irqs * 2;

Really, please drop this BITS_PER_LONG stuff. Use explicit numbers.

	M.
diff mbox series

Patch

diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
index f229e3e66387..880d1639aadc 100644
--- a/drivers/irqchip/irq-riscv-intc.c
+++ b/drivers/irqchip/irq-riscv-intc.c
@@ -16,6 +16,7 @@ 
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/smp.h>
+#include <asm/hwcap.h>
 
 static struct irq_domain *intc_domain;
 
@@ -29,6 +30,15 @@  static asmlinkage void riscv_intc_irq(struct pt_regs *regs)
 	generic_handle_domain_irq(intc_domain, cause);
 }
 
+static asmlinkage void riscv_intc_aia_irq(struct pt_regs *regs)
+{
+	unsigned long topi;
+
+	while ((topi = csr_read(CSR_TOPI)))
+		generic_handle_domain_irq(intc_domain,
+					  topi >> TOPI_IID_SHIFT);
+}
+
 /*
  * On RISC-V systems local interrupts are masked or unmasked by writing
  * the SIE (Supervisor Interrupt Enable) CSR.  As CSRs can only be written
@@ -38,12 +48,18 @@  static asmlinkage void riscv_intc_irq(struct pt_regs *regs)
 
 static void riscv_intc_irq_mask(struct irq_data *d)
 {
-	csr_clear(CSR_IE, BIT(d->hwirq));
+	if (d->hwirq < BITS_PER_LONG)
+		csr_clear(CSR_IE, BIT(d->hwirq));
+	else
+		csr_clear(CSR_IEH, BIT(d->hwirq - BITS_PER_LONG));
 }
 
 static void riscv_intc_irq_unmask(struct irq_data *d)
 {
-	csr_set(CSR_IE, BIT(d->hwirq));
+	if (d->hwirq < BITS_PER_LONG)
+		csr_set(CSR_IE, BIT(d->hwirq));
+	else
+		csr_set(CSR_IEH, BIT(d->hwirq - BITS_PER_LONG));
 }
 
 static void riscv_intc_irq_eoi(struct irq_data *d)
@@ -115,7 +131,7 @@  static struct fwnode_handle *riscv_intc_hwnode(void)
 static int __init riscv_intc_init(struct device_node *node,
 				  struct device_node *parent)
 {
-	int rc;
+	int rc, nr_irqs;
 	unsigned long hartid;
 
 	rc = riscv_of_parent_hartid(node, &hartid);
@@ -133,14 +149,21 @@  static int __init riscv_intc_init(struct device_node *node,
 	if (riscv_hartid_to_cpuid(hartid) != smp_processor_id())
 		return 0;
 
-	intc_domain = irq_domain_add_linear(node, BITS_PER_LONG,
+	nr_irqs = BITS_PER_LONG;
+	if (riscv_isa_extension_available(NULL, SxAIA) && BITS_PER_LONG == 32)
+		nr_irqs = nr_irqs * 2;
+
+	intc_domain = irq_domain_add_linear(node, nr_irqs,
 					    &riscv_intc_domain_ops, NULL);
 	if (!intc_domain) {
 		pr_err("unable to add IRQ domain\n");
 		return -ENXIO;
 	}
 
-	rc = set_handle_irq(&riscv_intc_irq);
+	if (riscv_isa_extension_available(NULL, SxAIA))
+		rc = set_handle_irq(&riscv_intc_aia_irq);
+	else
+		rc = set_handle_irq(&riscv_intc_irq);
 	if (rc) {
 		pr_err("failed to set irq handler\n");
 		return rc;
@@ -148,7 +171,9 @@  static int __init riscv_intc_init(struct device_node *node,
 
 	riscv_set_intc_hwnode_fn(riscv_intc_hwnode);
 
-	pr_info("%d local interrupts mapped\n", BITS_PER_LONG);
+	pr_info("%d local interrupts mapped%s\n",
+		nr_irqs, (riscv_isa_extension_available(NULL, SxAIA)) ?
+			 " using AIA" : "");
 
 	return 0;
 }