Aardvark HW does not support masking individual MSI interrupts. It supports
masking only whole equivalence classes which consist of MSI interrupts with
same lower 5 bits. So mask a whole equivalence class only if all interrupts
in this class are masked.
For each equivalence class store a reference counter to indicate how many
unmasked interrupts are in this class. Use this counter to decide when this
class of MSI interrupts can be masked.
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
Reviewed-by: Marek Behún <kabel@xxxxxxxxxx>
---
drivers/pci/controller/pci-aardvark.c | 77 ++++++++++++++++++++++++---
1 file changed, 69 insertions(+), 8 deletions(-)
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index d74e84b0e689..376f0666becc 100644
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -202,6 +202,7 @@ struct advk_pcie {
struct msi_domain_info msi_domain_info;
DECLARE_BITMAP(msi_used_linear, MSI_IRQ_LINEAR_COUNT);
struct list_head msi_used_radix;
+ u16 msi_used_ec_refcnt[32];
struct mutex msi_used_lock;
int link_gen;
struct pci_bridge_emul bridge;
@@ -405,12 +406,10 @@ static void advk_pcie_setup_hw(struct advk_pcie *pcie)
advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_REG);
advk_writel(pcie, PCIE_IRQ_ALL_MASK, HOST_CTRL_INT_STATUS_REG);
- /* Disable All ISR0/1 Sources */
+ /* Disable All ISR0/1 and MSI Sources */
advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_MASK_REG);
advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_MASK_REG);
-
- /* Unmask all MSIs */
- advk_writel(pcie, ~(u32)PCIE_MSI_ALL_MASK, PCIE_MSI_MASK_REG);
+ advk_writel(pcie, PCIE_MSI_ALL_MASK, PCIE_MSI_MASK_REG);
/* Unmask summary MSI interrupt */
reg = advk_readl(pcie, PCIE_ISR0_MASK_REG);
@@ -888,6 +887,54 @@ static int advk_msi_set_affinity(struct irq_data *irq_data,
return -EINVAL;
}
+static void advk_msi_irq_mask(struct irq_data *d)
+{
+ struct advk_pcie *pcie = d->domain->host_data;
+ irq_hw_number_t hwirq = irqd_to_hwirq(d);
+ u8 idx = hwirq & 31;
+ u32 mask;
+
+ /*
+ * Aardvark HW does not support masking individual MSI interrupts. It
+ * supports masking only whole equivalence class idx which consist of
+ * MSI interrupts with same low 5 bits. So mask equivalence class idx
+ * only in case there is no used (unmasked) interrupt in this class.
+ */
+
+ if (--pcie->msi_used_ec_refcnt[idx] > 0)
+ return;
+
+ mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
+ mask |= BIT(idx);
+ advk_writel(pcie, mask, PCIE_MSI_MASK_REG);
+}
+
+static void advk_msi_irq_unmask(struct irq_data *d)
+{
+ struct advk_pcie *pcie = d->domain->host_data;
+ irq_hw_number_t hwirq = irqd_to_hwirq(d);
+ u8 idx = hwirq & 31;
+ u32 mask;
+
+ pcie->msi_used_ec_refcnt[idx]++;
+
+ mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
+ mask &= ~BIT(idx);
+ advk_writel(pcie, mask, PCIE_MSI_MASK_REG);
+}
+
+static void advk_msi_top_irq_mask(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void advk_msi_top_irq_unmask(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
static int advk_msi_irq_domain_alloc(struct irq_domain *domain,
unsigned int virq,
unsigned int nr_irqs, void *args)
@@ -1025,9 +1072,13 @@ static int advk_pcie_init_msi_irq_domain(struct advk_pcie *pcie)
bottom_ic->name = "MSI";
bottom_ic->irq_compose_msi_msg = advk_msi_irq_compose_msi_msg;
bottom_ic->irq_set_affinity = advk_msi_set_affinity;
+ bottom_ic->irq_mask = advk_msi_irq_mask;
+ bottom_ic->irq_unmask = advk_msi_irq_unmask;
msi_ic = &pcie->msi_irq_chip;
msi_ic->name = "advk-MSI";
+ msi_ic->irq_mask = advk_msi_top_irq_mask;
+ msi_ic->irq_unmask = advk_msi_top_irq_unmask;
msi_di = &pcie->msi_domain_info;
msi_di->flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
@@ -1101,8 +1152,10 @@ static void advk_pcie_remove_irq_domain(struct advk_pcie *pcie)
static void advk_pcie_handle_msi(struct advk_pcie *pcie)
{
- u32 msi_val, msi_mask, msi_status, msi_idx;
+ struct irq_data *irq_data;
+ u32 msi_val, msi_mask, msi_status;
u16 msi_data;
+ u8 msi_idx;
int virq;
msi_mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
@@ -1119,11 +1172,19 @@ static void advk_pcie_handle_msi(struct advk_pcie *pcie)
*/
advk_writel(pcie, BIT(msi_idx), PCIE_MSI_STATUS_REG);
msi_data = advk_readl(pcie, PCIE_MSI_PAYLOAD_REG) & PCIE_MSI_DATA_MASK;
+
+ /*
+ * Aardvark HW does not support masking individual MSI interrupts.
+ * So call generic_handle_irq() only in case kernel has not masked
+ * received MSI interrupt.
+ */
virq = irq_find_mapping(pcie->msi_inner_domain, msi_data);
- if (virq)
- generic_handle_irq(virq);
- else
+ irq_data = virq ? irq_get_irq_data(virq) : NULL;
+
+ if (!irq_data)
dev_err(&pcie->pdev->dev, "unexpected MSI 0x%04hx\n", msi_data);
+ else if (!irqd_irq_masked(irq_data))
+ generic_handle_irq(virq);
}
advk_writel(pcie, PCIE_ISR0_MSI_INT_PENDING,
--
2.20.1
