[v13,03/13] irqchip/riscv-intc: Add support for RISC-V AIA

Commit Message

Anup Patel Feb. 20, 2024, 6:07 a.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

We add support for #1 and #2 described above in the RISC-V intc driver.

Signed-off-by: Anup Patel <[e-mail]>
---
 drivers/irqchip/irq-riscv-intc.c | 34 ++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

Comments

Thomas Gleixner Feb. 20, 2024, 10:13 a.m. UTC | #1

On Tue, Feb 20 2024 at 11:37, Anup Patel 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
>
> We add support for #1 and #2 described above in the RISC-V intc
> driver.

S/We add/Add/

> +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);

Please let it stick out. You got 100 characters. All over the place.

Thanks,

        tglx

Anup Patel Feb. 21, 2024, 1:32 p.m. UTC | #2

On Tue, Feb 20, 2024 at 3:43 PM Thomas Gleixner <[e-mail]> wrote:
>
> On Tue, Feb 20 2024 at 11:37, Anup Patel 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
> >
> > We add support for #1 and #2 described above in the RISC-V intc
> > driver.
>
> S/We add/Add/

Okay, I will update.

>
> > +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);
>
> Please let it stick out. You got 100 characters. All over the place.

Okay, I will update.

Regards,
Anup

Patch

diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
index e8d01b14ccdd..bab536bbaf2c 100644
--- a/drivers/irqchip/irq-riscv-intc.c
+++ b/drivers/irqchip/irq-riscv-intc.c
@@ -17,6 +17,7 @@ 
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/smp.h>
+#include <asm/hwcap.h>
 
 static struct irq_domain *intc_domain;
 
@@ -30,6 +31,15 @@  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
@@ -39,12 +49,18 @@  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 (IS_ENABLED(CONFIG_32BIT) && d->hwirq >= BITS_PER_LONG)
+		csr_clear(CSR_IEH, BIT(d->hwirq - BITS_PER_LONG));
+	else
+		csr_clear(CSR_IE, BIT(d->hwirq));
 }
 
 static void riscv_intc_irq_unmask(struct irq_data *d)
 {
-	csr_set(CSR_IE, BIT(d->hwirq));
+	if (IS_ENABLED(CONFIG_32BIT) && d->hwirq >= BITS_PER_LONG)
+		csr_set(CSR_IEH, BIT(d->hwirq - BITS_PER_LONG));
+	else
+		csr_set(CSR_IE, BIT(d->hwirq));
 }
 
 static void riscv_intc_irq_eoi(struct irq_data *d)
@@ -115,16 +131,20 @@  static struct fwnode_handle *riscv_intc_hwnode(void)
 
 static int __init riscv_intc_init_common(struct fwnode_handle *fn)
 {
-	int rc;
+	int rc, nr_irqs = riscv_isa_extension_available(NULL, SxAIA) ?
+			  64 : BITS_PER_LONG;
 
-	intc_domain = irq_domain_create_linear(fn, BITS_PER_LONG,
+	intc_domain = irq_domain_create_linear(fn, 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;
@@ -132,7 +152,9 @@  static int __init riscv_intc_init_common(struct fwnode_handle *fn)
 
 	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;
 }