Re: [PATCH v2 2/8] powerpc/xive: Introduce an IPI interrupt domain
On Wed, 3 Mar 2021 18:48:51 +0100
Cédric Le Goater wrote:
> The IPI interrupt is a special case of the XIVE IRQ domain. When
> mapping and unmapping the interrupts in the Linux interrupt number
> space, the HW interrupt number 0 (XIVE_IPI_HW_IRQ) is checked to
> distinguish the IPI interrupt from other interrupts of the system.
>
> Simplify the XIVE interrupt domain by introducing a specific domain
> for the IPI.
>
> Signed-off-by: Cédric Le Goater
> ---
Nice !
Reviewed-by: Greg Kurz
> arch/powerpc/sysdev/xive/common.c | 51 +--
> 1 file changed, 22 insertions(+), 29 deletions(-)
>
> diff --git a/arch/powerpc/sysdev/xive/common.c
> b/arch/powerpc/sysdev/xive/common.c
> index b8e456da28aa..e7783760d278 100644
> --- a/arch/powerpc/sysdev/xive/common.c
> +++ b/arch/powerpc/sysdev/xive/common.c
> @@ -63,6 +63,8 @@ static const struct xive_ops *xive_ops;
> static struct irq_domain *xive_irq_domain;
>
> #ifdef CONFIG_SMP
> +static struct irq_domain *xive_ipi_irq_domain;
> +
> /* The IPIs all use the same logical irq number */
> static u32 xive_ipi_irq;
> #endif
> @@ -1067,20 +1069,32 @@ static struct irq_chip xive_ipi_chip = {
> .irq_unmask = xive_ipi_do_nothing,
> };
>
> +/*
> + * IPIs are marked per-cpu. We use separate HW interrupts under the
> + * hood but associated with the same "linux" interrupt
> + */
> +static int xive_ipi_irq_domain_map(struct irq_domain *h, unsigned int virq,
> +irq_hw_number_t hw)
> +{
> + irq_set_chip_and_handler(virq, _ipi_chip, handle_percpu_irq);
> + return 0;
> +}
> +
> +static const struct irq_domain_ops xive_ipi_irq_domain_ops = {
> + .map = xive_ipi_irq_domain_map,
> +};
> +
> static void __init xive_request_ipi(void)
> {
> unsigned int virq;
>
> - /*
> - * Initialization failed, move on, we might manage to
> - * reach the point where we display our errors before
> - * the system falls appart
> - */
> - if (!xive_irq_domain)
> + xive_ipi_irq_domain = irq_domain_add_linear(NULL, 1,
> + _ipi_irq_domain_ops,
> NULL);
> + if (WARN_ON(xive_ipi_irq_domain == NULL))
> return;
>
> /* Initialize it */
> - virq = irq_create_mapping(xive_irq_domain, XIVE_IPI_HW_IRQ);
> + virq = irq_create_mapping(xive_ipi_irq_domain, XIVE_IPI_HW_IRQ);
> xive_ipi_irq = virq;
>
> WARN_ON(request_irq(virq, xive_muxed_ipi_action,
> @@ -1178,19 +1192,6 @@ static int xive_irq_domain_map(struct irq_domain *h,
> unsigned int virq,
>*/
> irq_clear_status_flags(virq, IRQ_LEVEL);
>
> -#ifdef CONFIG_SMP
> - /* IPIs are special and come up with HW number 0 */
> - if (hw == XIVE_IPI_HW_IRQ) {
> - /*
> - * IPIs are marked per-cpu. We use separate HW interrupts under
> - * the hood but associated with the same "linux" interrupt
> - */
> - irq_set_chip_and_handler(virq, _ipi_chip,
> - handle_percpu_irq);
> - return 0;
> - }
> -#endif
> -
> rc = xive_irq_alloc_data(virq, hw);
> if (rc)
> return rc;
> @@ -1202,15 +1203,7 @@ static int xive_irq_domain_map(struct irq_domain *h,
> unsigned int virq,
>
> static void xive_irq_domain_unmap(struct irq_domain *d, unsigned int virq)
> {
> - struct irq_data *data = irq_get_irq_data(virq);
> - unsigned int hw_irq;
> -
> - /* XXX Assign BAD number */
> - if (!data)
> - return;
> - hw_irq = (unsigned int)irqd_to_hwirq(data);
> - if (hw_irq != XIVE_IPI_HW_IRQ)
> - xive_irq_free_data(virq);
> + xive_irq_free_data(virq);
> }
>
> static int xive_irq_domain_xlate(struct irq_domain *h, struct device_node
> *ct,
[PATCH v2 2/8] powerpc/xive: Introduce an IPI interrupt domain
The IPI interrupt is a special case of the XIVE IRQ domain. When
mapping and unmapping the interrupts in the Linux interrupt number
space, the HW interrupt number 0 (XIVE_IPI_HW_IRQ) is checked to
distinguish the IPI interrupt from other interrupts of the system.
Simplify the XIVE interrupt domain by introducing a specific domain
for the IPI.
Signed-off-by: Cédric Le Goater
---
arch/powerpc/sysdev/xive/common.c | 51 +--
1 file changed, 22 insertions(+), 29 deletions(-)
diff --git a/arch/powerpc/sysdev/xive/common.c
b/arch/powerpc/sysdev/xive/common.c
index b8e456da28aa..e7783760d278 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -63,6 +63,8 @@ static const struct xive_ops *xive_ops;
static struct irq_domain *xive_irq_domain;
#ifdef CONFIG_SMP
+static struct irq_domain *xive_ipi_irq_domain;
+
/* The IPIs all use the same logical irq number */
static u32 xive_ipi_irq;
#endif
@@ -1067,20 +1069,32 @@ static struct irq_chip xive_ipi_chip = {
.irq_unmask = xive_ipi_do_nothing,
};
+/*
+ * IPIs are marked per-cpu. We use separate HW interrupts under the
+ * hood but associated with the same "linux" interrupt
+ */
+static int xive_ipi_irq_domain_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler(virq, _ipi_chip, handle_percpu_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops xive_ipi_irq_domain_ops = {
+ .map = xive_ipi_irq_domain_map,
+};
+
static void __init xive_request_ipi(void)
{
unsigned int virq;
- /*
-* Initialization failed, move on, we might manage to
-* reach the point where we display our errors before
-* the system falls appart
-*/
- if (!xive_irq_domain)
+ xive_ipi_irq_domain = irq_domain_add_linear(NULL, 1,
+ _ipi_irq_domain_ops,
NULL);
+ if (WARN_ON(xive_ipi_irq_domain == NULL))
return;
/* Initialize it */
- virq = irq_create_mapping(xive_irq_domain, XIVE_IPI_HW_IRQ);
+ virq = irq_create_mapping(xive_ipi_irq_domain, XIVE_IPI_HW_IRQ);
xive_ipi_irq = virq;
WARN_ON(request_irq(virq, xive_muxed_ipi_action,
@@ -1178,19 +1192,6 @@ static int xive_irq_domain_map(struct irq_domain *h,
unsigned int virq,
*/
irq_clear_status_flags(virq, IRQ_LEVEL);
-#ifdef CONFIG_SMP
- /* IPIs are special and come up with HW number 0 */
- if (hw == XIVE_IPI_HW_IRQ) {
- /*
-* IPIs are marked per-cpu. We use separate HW interrupts under
-* the hood but associated with the same "linux" interrupt
-*/
- irq_set_chip_and_handler(virq, _ipi_chip,
-handle_percpu_irq);
- return 0;
- }
-#endif
-
rc = xive_irq_alloc_data(virq, hw);
if (rc)
return rc;
@@ -1202,15 +1203,7 @@ static int xive_irq_domain_map(struct irq_domain *h,
unsigned int virq,
static void xive_irq_domain_unmap(struct irq_domain *d, unsigned int virq)
{
- struct irq_data *data = irq_get_irq_data(virq);
- unsigned int hw_irq;
-
- /* XXX Assign BAD number */
- if (!data)
- return;
- hw_irq = (unsigned int)irqd_to_hwirq(data);
- if (hw_irq != XIVE_IPI_HW_IRQ)
- xive_irq_free_data(virq);
+ xive_irq_free_data(virq);
}
static int xive_irq_domain_xlate(struct irq_domain *h, struct device_node *ct,
--
2.26.2
