[PATCH v2 1/3] lib: utils: irqchip: implement APLIC hwirq operation hooks
Raymond Mao
raymondmaoca at gmail.com
Tue Jun 16 13:30:54 PDT 2026
Hi Anup,
On Thu, Jun 11, 2026 at 1:15 AM Anup Patel <anup at brainfault.org> wrote:
>
> Hi Ray,
>
> On Mon, May 4, 2026 at 10:43 PM Raymond Mao <raymondmaoca at gmail.com> wrote:
> >
> > From: Raymond Mao <raymond.mao at riscstar.com>
> >
> > Implement the APLIC hardware interrupt hooks used by the generic
> > irqchip framework for M-mode direct-mode wired interrupts.
> >
> > Program a minimal APLIC direct-mode configuration during hwirq setup
> > and claim external interrupts via IDC.CLAIMI. Add the helper logic
> > needed to derive the source ID from CLAIMI, map hart index to IDC
> > index, skip delegated interrupts, and register process_hwirqs()
> > only for the M-mode direct-mode provider.
> >
> > Signed-off-by: Raymond Mao <raymond.mao at riscstar.com>
>
> Pawandeep Oza (CC'ed) has developed functionally complete IMSIC
> and APLIC drivers for OpenSBI which supports both MSI-mode and
> Direct-mode of APLIC. He did include some of your changes from
> this patch. He will send-out his series pretty soon so stay tuned.
>
Sorry but I didn't find Pawandeep Oza from the CC list.
But anyway, can he rebase on my commit instead of just picking changes
from my patch?
Thanks and regards,
Raymond
> Regards,
> Anup
>
> > ---
> > lib/utils/irqchip/aplic.c | 227 ++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 227 insertions(+)
> >
> > diff --git a/lib/utils/irqchip/aplic.c b/lib/utils/irqchip/aplic.c
> > index ec69c82b..3f4991b5 100644
> > --- a/lib/utils/irqchip/aplic.c
> > +++ b/lib/utils/irqchip/aplic.c
> > @@ -245,6 +245,220 @@ static int aplic_check_msicfg(struct aplic_msicfg_data *msicfg)
> > return 0;
> > }
> >
> > +static inline void *aplic_idc_base(unsigned long aplic_addr, u32 idc_index)
> > +{
> > + return (void *)(aplic_addr + APLIC_IDC_BASE +
> > + (unsigned long)idc_index * APLIC_IDC_SIZE);
> > +}
> > +
> > +static inline struct aplic_data *aplic_irqchip_to_data(struct sbi_irqchip_device *chip)
> > +{
> > + return container_of(chip, struct aplic_data, irqchip);
> > +}
> > +
> > +static bool aplic_hwirq_delegated(const struct aplic_data *aplic, u32 hwirq)
> > +{
> > + u32 i;
> > +
> > + for (i = 0; i < APLIC_MAX_DELEGATE; i++) {
> > + const struct aplic_delegate_data *deleg = &aplic->delegate[i];
> > +
> > + if (!deleg->first_irq || !deleg->last_irq)
> > + continue;
> > + if (deleg->first_irq <= hwirq && hwirq <= deleg->last_irq)
> > + return true;
> > + }
> > +
> > + return false;
> > +}
> > +
> > +static bool aplic_mmode_direct(const struct aplic_data *aplic)
> > +{
> > + return aplic->targets_mmode && aplic->num_idc;
> > +}
> > +
> > +static int aplic_hartindex_to_idc_index(const struct aplic_data *aplic,
> > + u32 hartindex)
> > +{
> > + u32 i;
> > +
> > + if (!aplic->num_idc)
> > + return SBI_ENODEV;
> > +
> > + if (aplic->idc_map) {
> > + for (i = 0; i < aplic->num_idc; i++) {
> > + if (aplic->idc_map[i] == hartindex)
> > + return i;
> > + }
> > +
> > + return SBI_ENODEV;
> > + }
> > +
> > + if (hartindex < aplic->num_idc)
> > + return hartindex;
> > +
> > + return SBI_ENODEV;
> > +}
> > +
> > +static int aplic_hwirq_target_idc_index(struct sbi_irqchip_device *chip)
> > +{
> > + u32 hartindex = current_hartindex();
> > +
> > + if (!sbi_hartmask_test_hartindex(hartindex, &chip->target_harts)) {
> > + sbi_hartmask_for_each_hartindex(hartindex, &chip->target_harts)
> > + break;
> > + if (hartindex >= SBI_HARTMASK_MAX_BITS)
> > + return SBI_ENODEV;
> > + }
> > +
> > + return aplic_hartindex_to_idc_index(aplic_irqchip_to_data(chip),
> > + hartindex);
> > +}
> > +
> > +static u32 aplic_domaincfg_value(void)
> > +{
> > + u32 val = APLIC_DOMAINCFG_IE;
> > +
> > +#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> > + val |= APLIC_DOMAINCFG_BE;
> > +#endif
> > +
> > + return val;
> > +}
> > +
> > +static void aplic_hwirq_mask(struct sbi_irqchip_device *chip, u32 hwirq)
> > +{
> > + struct aplic_data *aplic = aplic_irqchip_to_data(chip);
> > +
> > + if (!hwirq || aplic_hwirq_delegated(aplic, hwirq))
> > + return;
> > +
> > + if (!aplic->addr || hwirq > aplic->num_source)
> > + return;
> > +
> > + /* Disable source */
> > + writel(hwirq, (void *)(aplic->addr + APLIC_CLRIENUM));
> > +}
> > +
> > +static void aplic_hwirq_unmask(struct sbi_irqchip_device *chip, u32 hwirq)
> > +{
> > + struct aplic_data *aplic = aplic_irqchip_to_data(chip);
> > +
> > + if (!hwirq || aplic_hwirq_delegated(aplic, hwirq))
> > + return;
> > +
> > + if (!aplic->addr || hwirq > aplic->num_source)
> > + return;
> > +
> > + /* Enable source */
> > + writel(hwirq, (void *)(aplic->addr + APLIC_SETIENUM));
> > +}
> > +
> > +static int aplic_hwirq_claim(struct sbi_irqchip_device *chip, u32 *hwirq)
> > +{
> > + struct aplic_data *aplic = aplic_irqchip_to_data(chip);
> > + int idc_index;
> > + void *idc;
> > + u32 v, id;
> > +
> > + if (!hwirq)
> > + return SBI_EINVAL;
> > +
> > + idc_index = aplic_hartindex_to_idc_index(aplic, current_hartindex());
> > + if (!aplic->addr || idc_index < 0)
> > + return SBI_ENODEV;
> > +
> > + idc = aplic_idc_base(aplic->addr, idc_index);
> > +
> > + /*
> > + * Read CLAIMI: returns TOPI value.
> > + * ID==0 means spurious interrupt (spec-defined).
> > + */
> > + v = readl(idc + APLIC_IDC_CLAIMI); /* dequeue */
> > +
> > + id = (v >> APLIC_IDC_TOPI_ID_SHIFT) & APLIC_IDC_TOPI_ID_MASK;
> > +
> > + /* ID==0 means spurious / no pending wired interrupt */
> > + if (!id)
> > + return SBI_ENOENT;
> > +
> > + /* Bound check against DT-discovered num_src */
> > + if (id > aplic->num_source)
> > + return SBI_EINVAL;
> > +
> > + *hwirq = id;
> > +
> > + return SBI_OK;
> > +}
> > +
> > +static int aplic_hwirq_setup(struct sbi_irqchip_device *chip, u32 hwirq)
> > +{
> > + struct aplic_data *aplic = aplic_irqchip_to_data(chip);
> > + unsigned long idc;
> > + int idc_index;
> > +
> > + if (!hwirq || hwirq > aplic->num_source)
> > + return SBI_EINVAL;
> > + if (!aplic_mmode_direct(aplic))
> > + return SBI_ENOTSUPP;
> > + if (aplic_hwirq_delegated(aplic, hwirq))
> > + return SBI_ENOTSUPP;
> > +
> > + idc_index = aplic_hwirq_target_idc_index(chip);
> > + if (idc_index < 0)
> > + return idc_index;
> > +
> > + idc = aplic->addr + APLIC_IDC_BASE + idc_index * APLIC_IDC_SIZE;
> > +
> > + /* APLIC: sourcecfg/target/enable */
> > + writel(APLIC_SOURCECFG_SM_LEVEL_HIGH,
> > + (void *)(aplic->addr + APLIC_SOURCECFG_BASE + (hwirq - 1) * 4));
> > +
> > + writel(((u32)idc_index << APLIC_TARGET_HART_IDX_SHIFT) |
> > + APLIC_DEFAULT_PRIORITY,
> > + (void *)(aplic->addr + APLIC_TARGET_BASE + (hwirq - 1) * 4));
> > +
> > + writel(hwirq, (void *)(aplic->addr + APLIC_SETIENUM));
> > +
> > + /* Direct mode for aia=aplic: DM=0 => don't set DM bit */
> > + writel(aplic_domaincfg_value(), (void *)(aplic->addr + APLIC_DOMAINCFG));
> > +
> > + /* IDC delivery */
> > + writel(APLIC_ENABLE_IDELIVERY, (void *)(idc + APLIC_IDC_IDELIVERY));
> > + writel(APLIC_ENABLE_ITHRESHOLD, (void *)(idc + APLIC_IDC_ITHRESHOLD));
> > +
> > + return SBI_OK;
> > +}
> > +
> > +static int aplic_process_hwirqs(struct sbi_irqchip_device *chip)
> > +{
> > + if (!chip)
> > + return SBI_ENODEV;
> > +
> > + for (;;) {
> > + u32 hwirq = 0;
> > + int rc = aplic_hwirq_claim(chip, &hwirq);
> > +
> > + if (rc == SBI_ENOENT)
> > + break;
> > + if (rc)
> > + return rc;
> > +
> > + if (!hwirq)
> > + break;
> > +
> > + if (hwirq > chip->num_hwirq) {
> > + return SBI_EINVAL;
> > + }
> > +
> > + rc = sbi_irqchip_process_hwirq(chip, hwirq);
> > + if (rc)
> > + return rc;
> > + }
> > +
> > + return SBI_OK;
> > +}
> > +
> > int aplic_cold_irqchip_init(struct aplic_data *aplic)
> > {
> > int rc;
> > @@ -308,6 +522,19 @@ int aplic_cold_irqchip_init(struct aplic_data *aplic)
> > /* Register irqchip device */
> > aplic->irqchip.id = aplic->unique_id;
> > aplic->irqchip.num_hwirq = aplic->num_source + 1;
> > + aplic->irqchip.hwirq_mask = aplic_hwirq_mask;
> > + aplic->irqchip.hwirq_unmask = aplic_hwirq_unmask;
> > + /*
> > + * Only the domain that directly injects interrupts into M-mode external
> > + * interrupt line should provide process_hwirqs().
> > + *
> > + * The other domain (e.g. S-mode) may still be registered so that its
> > + * other ops (mask/unmask/config/etc.) can be used, but it must not
> > + * claim to be the external interrupt line provider.
> > + */
> > + if (aplic_mmode_direct(aplic))
> > + aplic->irqchip.process_hwirqs = aplic_process_hwirqs;
> > + aplic->irqchip.hwirq_setup = aplic_hwirq_setup;
> > rc = sbi_irqchip_add_device(&aplic->irqchip);
> > if (rc)
> > return rc;
> > --
> > 2.25.1
> >
More information about the opensbi
mailing list