Hi Volodymyr,
Thank you for your close review.
On 21.08.25 19:16, Volodymyr Babchuk wrote:
>
> Hi,
>
> Leonid Komarianskyi <leonid_komarians...@epam.com> writes:
>
>> Introduced appropriate register definitions, helper macros,
>> and initialization of required GICv3.1 distributor registers
>> to support eSPI. This type of interrupt is handled in the
>> same way as regular SPI interrupts, with the following
>> differences:
>>
>> 1) eSPIs can have up to 1024 interrupts, starting from the
>> beginning of the range, whereas regular SPIs use INTIDs from
>> 32 to 1019, totaling 988 interrupts;
>> 2) eSPIs start at INTID 4096, necessitating additional interrupt
>> index conversion during register operations.
>>
>> In case if appropriate config is disabled, or GIC HW doesn't
>> support eSPI, the existing functionality will remain the same.
>>
>> Signed-off-by: Leonid Komarianskyi <leonid_komarians...@epam.com>
>>
>> ---
>> Changes in V2:
>> - move gic_number_espis function from
>> [PATCH 08/10] xen/arm: vgic: add resource management for extended SPIs
>> to use it in the newly introduced gic_is_valid_espi
>> - add gic_is_valid_espi which checks if IRQ number is in supported
>> by HW eSPI range
>> - update gic_is_valid_irq conditions to allow operations with eSPIs
>> ---
>> xen/arch/arm/gic-v3.c | 73 ++++++++++++++++++++++++++
>> xen/arch/arm/include/asm/gic.h | 17 ++++++
>> xen/arch/arm/include/asm/gic_v3_defs.h | 33 ++++++++++++
>> 3 files changed, 123 insertions(+)
>>
>> diff --git a/xen/arch/arm/gic-v3.c b/xen/arch/arm/gic-v3.c
>> index 8fd78aba44..a0e8ee1a1e 100644
>> --- a/xen/arch/arm/gic-v3.c
>> +++ b/xen/arch/arm/gic-v3.c
>> @@ -485,6 +485,36 @@ static void __iomem *get_addr_by_offset(struct irq_desc
>> *irqd, u32 offset)
>> default:
>> break;
>> }
>> +#ifdef CONFIG_GICV3_ESPI
>> + case ESPI_BASE_INTID ... ESPI_MAX_INTID:
>> + {
>> + u32 irq_index = ESPI_INTID2IDX(irqd->irq);
>> +
>> + switch ( offset )
>> + {
>> + case GICD_ISENABLER:
>> + return (GICD + GICD_ISENABLERnE + (irq_index / 32) * 4);
>> + case GICD_ICENABLER:
>> + return (GICD + GICD_ICENABLERnE + (irq_index / 32) * 4);
>> + case GICD_ISPENDR:
>> + return (GICD + GICD_ISPENDRnE + (irq_index / 32) * 4);
>> + case GICD_ICPENDR:
>> + return (GICD + GICD_ICPENDRnE + (irq_index / 32) * 4);
>> + case GICD_ISACTIVER:
>> + return (GICD + GICD_ISACTIVERnE + (irq_index / 32) * 4);
>> + case GICD_ICACTIVER:
>> + return (GICD + GICD_ICACTIVERnE + (irq_index / 32) * 4);
>> + case GICD_ICFGR:
>> + return (GICD + GICD_ICFGRnE + (irq_index / 16) * 4);
>> + case GICD_IROUTER:
>> + return (GICD + GICD_IROUTERnE + irq_index * 8);
>> + case GICD_IPRIORITYR:
>> + return (GICD + GICD_IPRIORITYRnE + irq_index);
>> + default:
>> + break;
>> + }
>> + }
>> +#endif
>> default:
>> break;
>> }
>> @@ -645,6 +675,40 @@ static void gicv3_set_irq_priority(struct irq_desc
>> *desc,
>> spin_unlock(&gicv3.lock);
>> }
>>
>> +#ifdef CONFIG_GICV3_ESPI
>> +unsigned int gic_number_espis(void)
>> +{
>> + return gic_hw_ops->info->nr_espi;
>> +}
>> +
>> +static void gicv3_dist_espi_common_init(uint32_t type)
>> +{
>> + unsigned int espi_nr;
>> + int i;
>> +
>> + espi_nr = min(1024U, GICD_TYPER_ESPIS_NUM(type));
>> + gicv3_info.nr_espi = espi_nr;
>> + /* The GIC HW doesn't support eSPI, so we can leave from here */
>> + if ( gicv3_info.nr_espi == 0 )
>> + return;
>> +
>> + for ( i = 0; i < espi_nr; i += 16 )
>> + writel_relaxed(0, GICD + GICD_ICFGRnE + (i / 16) * 4);
>> +
>> + for ( i = 0; i < espi_nr; i += 4 )
>> + writel_relaxed(GIC_PRI_IRQ_ALL, GICD + GICD_IPRIORITYRnE + (i / 4)
>> * 4);
>> +
>> + for ( i = 0; i < espi_nr; i += 32 )
>> + {
>> + writel_relaxed(0xffffffffU, GICD + GICD_ICENABLERnE + (i / 32) * 4);
>
> Is there are particular reason why you use GENMASK(31,0) below, but
> open-coded 0xffffffff here?
>
>> + writel_relaxed(0xffffffffU, GICD + GICD_ICACTIVERnE + (i / 32) * 4);
>
> ... and here?
>
No, there is no particular reason to use open-code here. It is just a
copy-paste from the code for regular SPI initialization. Thus, I agree
it is much better to use GENMASK(31, 0). I will change this in V3.
>> + }
>> +
>> + for ( i = 0; i < espi_nr; i += 32 )
>> + writel_relaxed(GENMASK(31, 0), GICD + GICD_IGROUPRnE + (i / 32) *
>> 4);
>> +}
>> +#endif
>> +
>> static void __init gicv3_dist_init(void)
>> {
>> uint32_t type;
>> @@ -690,6 +754,10 @@ static void __init gicv3_dist_init(void)
>> for ( i = NR_GIC_LOCAL_IRQS; i < nr_lines; i += 32 )
>> writel_relaxed(GENMASK(31, 0), GICD + GICD_IGROUPR + (i / 32) * 4);
>>
>> +#ifdef CONFIG_GICV3_ESPI
>> + gicv3_dist_espi_common_init(type);
>> +#endif
>> +
>> gicv3_dist_wait_for_rwp();
>>
>> /* Turn on the distributor */
>> @@ -703,6 +771,11 @@ static void __init gicv3_dist_init(void)
>>
>> for ( i = NR_GIC_LOCAL_IRQS; i < nr_lines; i++ )
>> writeq_relaxed_non_atomic(affinity, GICD + GICD_IROUTER + i * 8);
>> +
>> +#ifdef CONFIG_GICV3_ESPI
>> + for ( i = 0; i < gicv3_info.nr_espi; i++ )
>> + writeq_relaxed_non_atomic(affinity, GICD + GICD_IROUTERnE + i * 8);
>> +#endif
>> }
>>
>> static int gicv3_enable_redist(void)
>> diff --git a/xen/arch/arm/include/asm/gic.h b/xen/arch/arm/include/asm/gic.h
>> index ac0b7b783e..2f570abf70 100644
>> --- a/xen/arch/arm/include/asm/gic.h
>> +++ b/xen/arch/arm/include/asm/gic.h
>> @@ -306,8 +306,21 @@ extern void gic_dump_vgic_info(struct vcpu *v);
>>
>> /* Number of interrupt lines */
>> extern unsigned int gic_number_lines(void);
>> +#ifdef CONFIG_GICV3_ESPI
>> +extern unsigned int gic_number_espis(void);
>> +
>> +static inline bool gic_is_valid_espi(unsigned int irq)
>> +{
>> + return (irq >= ESPI_BASE_INTID && irq <
>> ESPI_IDX2INTID(gic_number_espis()));
>> +}
>> +#endif
>> +
>> static inline bool gic_is_valid_irq(unsigned int irq)
>> {
>> +#ifdef CONFIG_GICV3_ESPI
>> + if ( gic_is_valid_espi(irq) )
>> + return true;
>> +#endif
>> return irq < gic_number_lines();
>> }
>>
>> @@ -325,6 +338,10 @@ struct gic_info {
>> enum gic_version hw_version;
>> /* Number of GIC lines supported */
>> unsigned int nr_lines;
>> +#ifdef CONFIG_GICV3_ESPI
>> + /* Number of GIC eSPI supported */
>> + unsigned int nr_espi;
>> +#endif
>> /* Number of LR registers */
>> uint8_t nr_lrs;
>> /* Maintenance irq number */
>> diff --git a/xen/arch/arm/include/asm/gic_v3_defs.h
>> b/xen/arch/arm/include/asm/gic_v3_defs.h
>> index 2af093e774..7f769b38e3 100644
>> --- a/xen/arch/arm/include/asm/gic_v3_defs.h
>> +++ b/xen/arch/arm/include/asm/gic_v3_defs.h
>> @@ -37,6 +37,39 @@
>> #define GICD_IROUTER1019 (0x7FD8)
>> #define GICD_PIDR2 (0xFFE8)
>>
>> +#ifdef CONFIG_GICV3_ESPI
>> +/* Additional registers for GICv3.1 */
>> +#define GICD_IGROUPRnE (0x1000)
>> +#define GICD_IGROUPRnEN (0x107C)
>> +#define GICD_ISENABLERnE (0x1200)
>> +#define GICD_ISENABLERnEN (0x127C)
>> +#define GICD_ICENABLERnE (0x1400)
>> +#define GICD_ICENABLERnEN (0x147C)
>> +#define GICD_ISPENDRnE (0x1600)
>> +#define GICD_ISPENDRnEN (0x167C)
>> +#define GICD_ICPENDRnE (0x1800)
>> +#define GICD_ICPENDRnEN (0x187C)
>> +#define GICD_ISACTIVERnE (0x1A00)
>> +#define GICD_ISACTIVERnEN (0x1A7C)
>> +#define GICD_ICACTIVERnE (0x1C00)
>> +#define GICD_ICACTIVERnEN (0x1C7C)
>> +#define GICD_IPRIORITYRnE (0x2000)
>> +#define GICD_IPRIORITYRnEN (0x23FC)
>> +#define GICD_ICFGRnE (0x3000)
>> +#define GICD_ICFGRnEN (0x30FC)
>> +#define GICD_IROUTERnE (0x8000)
>> +#define GICD_IROUTERnEN (0x9FFC)
>> +
>> +#define GICD_TYPER_ESPI_SHIFT 8
>> +#define GICD_TYPER_ESPI_RANGE_SHIFT 27
>> +#define GICD_TYPER_ESPI_RANGE_MASK (0x1F)
>> +#define GICD_TYPER_ESPI (1U << GICD_TYPER_ESPI_SHIFT)
>> +#define GICD_TYPER_ESPI_RANGE(typer) ((((typer) &
>> GICD_TYPER_ESPI_RANGE_MASK) + 1) * 32)
>
> Isn't this line a bit long?
>
Yes, I will revise all patches in the series with such long lines and
fix them in V3.
>> +#define GICD_TYPER_ESPIS_NUM(typer) \
>> + (((typer) & GICD_TYPER_ESPI) ? \
>> + GICD_TYPER_ESPI_RANGE((typer) >> GICD_TYPER_ESPI_RANGE_SHIFT) : 0)
>
> I am not sure that this is correct.
>
> Probably you wanted to write
> + GICD_TYPER_ESPI_RANGE((typer >> GICD_TYPER_ESPI_RANGE_SHIFT)) : 0)
>
>
I double checked - it seems like everything is correct - the typer
parameter should be surrounded by parentheses, and GICD_TYPER_ESPI_RANGE
should operate with the already shifted value. However, I wrote a
slightly confusing macro. At the very least, it would be better to
rename in V3 the typer parameter in GICD_TYPER_ESPI_RANGE, because it
takes the value of GICD_TYPER that is already shifted by 27, instead of
the raw register value. Would that be acceptable?
>> +#endif
>> +
>> /* Common between GICD_PIDR2 and GICR_PIDR2 */
>> #define GIC_PIDR2_ARCH_MASK (0xf0)
>> #define GIC_PIDR2_ARCH_GICv3 (0x30)
>
Best regards,
Leonid
