[PATCH v2 1/5] PCI: brcmstb: Enable Multi-MSI

From: Jim Quinlan
Date: Tue Oct 11 2022 - 14:42:23 EST


We always wanted to enable Multi-MSI but didn't have a test device until
recently. In addition, there are some devices out there that will ask for
multiple MSI but refuse to work if they are only granted one.

Signed-off-by: Jim Quinlan <jim2101024@xxxxxxxxx>
Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
drivers/pci/controller/pcie-brcmstb.c | 26 +++++++++++++++-----------
1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 521acd632f1a..a45ce7d61847 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -445,7 +445,8 @@ static struct irq_chip brcm_msi_irq_chip = {

static struct msi_domain_info brcm_msi_domain_info = {
/* Multi MSI is supported by the controller, but not by this driver */
- .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI),
.chip = &brcm_msi_irq_chip,
};

@@ -505,21 +506,23 @@ static struct irq_chip brcm_msi_bottom_irq_chip = {
.irq_ack = brcm_msi_ack_irq,
};

-static int brcm_msi_alloc(struct brcm_msi *msi)
+static int brcm_msi_alloc(struct brcm_msi *msi, unsigned int nr_irqs)
{
int hwirq;

mutex_lock(&msi->lock);
- hwirq = bitmap_find_free_region(msi->used, msi->nr, 0);
+ hwirq = bitmap_find_free_region(msi->used, msi->nr,
+ order_base_2(nr_irqs));
mutex_unlock(&msi->lock);

return hwirq;
}

-static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq)
+static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq,
+ unsigned int nr_irqs)
{
mutex_lock(&msi->lock);
- bitmap_release_region(msi->used, hwirq, 0);
+ bitmap_release_region(msi->used, hwirq, order_base_2(nr_irqs));
mutex_unlock(&msi->lock);
}

@@ -527,16 +530,17 @@ static int brcm_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *args)
{
struct brcm_msi *msi = domain->host_data;
- int hwirq;
+ int hwirq, i;

- hwirq = brcm_msi_alloc(msi);
+ hwirq = brcm_msi_alloc(msi, nr_irqs);

if (hwirq < 0)
return hwirq;

- irq_domain_set_info(domain, virq, (irq_hw_number_t)hwirq,
- &brcm_msi_bottom_irq_chip, domain->host_data,
- handle_edge_irq, NULL, NULL);
+ for (i = 0; i < nr_irqs; i++)
+ irq_domain_set_info(domain, virq + i, hwirq + i,
+ &brcm_msi_bottom_irq_chip, domain->host_data,
+ handle_edge_irq, NULL, NULL);
return 0;
}

@@ -546,7 +550,7 @@ static void brcm_irq_domain_free(struct irq_domain *domain,
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
struct brcm_msi *msi = irq_data_get_irq_chip_data(d);

- brcm_msi_free(msi, d->hwirq);
+ brcm_msi_free(msi, d->hwirq, nr_irqs);
}

static const struct irq_domain_ops msi_domain_ops = {
--
2.17.1