From: Suravee Suthikulpanit <Suravee.Suthikulpanit@xxxxxxx>
This patch extend GICv2m MSI to support multiple MSI in ARM64.
This requires the common arch_setup_msi_irqs() to be overwriten
with ARM64 version which does not return 1 for PCI_CAP_ID_MSI and
nvec > 1.
Cc: Mark Rutland <Mark.Rutland@xxxxxxx>
Cc: Marc Zyngier <Marc.Zyngier@xxxxxxx>
Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
Cc: Catalin Marinas <Catalin.Marinas@xxxxxxx>
Cc: Will Deacon <Will.Deacon@xxxxxxx>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@xxxxxxx>
---
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/msi.c | 41 ++++++++++++++++++++
drivers/irqchip/irq-gic-v2m.c | 87 ++++++++++++++++++++++++++++++++++++++-----
3 files changed, 119 insertions(+), 10 deletions(-)
create mode 100644 arch/arm64/kernel/msi.c
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index df7ef87..a921c42 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -29,6 +29,7 @@ arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o
arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o
arm64-obj-$(CONFIG_KGDB) += kgdb.o
arm64-obj-$(CONFIG_EFI) += efi.o efi-stub.o efi-entry.o
+arm64-obj-$(CONFIG_PCI_MSI) += msi.o
obj-y += $(arm64-obj-y) vdso/
obj-m += $(arm64-obj-m)
diff --git a/arch/arm64/kernel/msi.c b/arch/arm64/kernel/msi.c
new file mode 100644
index 0000000..a295862
--- /dev/null
+++ b/arch/arm64/kernel/msi.c
@@ -0,0 +1,41 @@
+/*
+ * ARM64 architectural MSI implemention
+ *
+ * Support for Message Signalelled Interrupts for systems that
+ * implement ARM Generic Interrupt Controller: GICv2m.
+ *
+ * Copyright (C) 2014 Advanced Micro Devices, Inc.
+ * Authors: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/irq.h>
+#include <linux/msi.h>
+#include <linux/pci.h>
+
+/*
+ * ARM64 function for seting up MSI irqs.
+ * Based on driver/pci/msi.c: arch_setup_msi_irqs().
+ *
+ * Note:
+ * Current implementation assumes that all interrupt controller used in
+ * ARM64 architecture _MUST_ supports multi-MSI.
+ */
+int arm64_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+ struct msi_desc *entry;
+ int ret;
+
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ ret = arch_setup_msi_irq(dev, entry);
+ if (ret < 0)
+ return ret;
+ if (ret > 0)
+ return -ENOSPC;
+ }
+
+ return 0;
+}
diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c
index 2471e4c..7b52e67 100644
--- a/drivers/irqchip/irq-gic-v2m.c
+++ b/drivers/irqchip/irq-gic-v2m.c
@@ -99,13 +99,26 @@ static void gicv2m_teardown_msi_irq(struct msi_chip *chip, unsigned int irq)
spin_unlock(&data->msi_cnt_lock);
}
+static int gicv2m_msi_get_vec_count(struct pci_dev *pdev, struct msi_desc *desc)
+{
+ int ret = -EINVAL;
+#ifdef CONFIG_PCI_MSI
+ if (desc->msi_attrib.is_msix)
+ ret = pci_msix_vec_count(pdev);
+ else
+ ret = pci_msi_vec_count(pdev);
+#endif
+ return ret;
+}
+
static int gicv2m_setup_msi_irq(struct msi_chip *chip,
struct pci_dev *pdev,
struct msi_desc *desc)
{
- int irq, avail;
+ int i, irq, nvec, avail;
struct msi_msg msg;
phys_addr_t addr;
+ struct msi_desc *entry;
struct v2m_data *data = container_of(chip, struct v2m_data, msi_chip);
if (!desc) {
@@ -114,16 +127,70 @@ static int gicv2m_setup_msi_irq(struct msi_chip *chip,
return -EINVAL;
}
- avail = alloc_msi_irq(data, 1, &irq);
- if (avail != 0) {
- dev_err(&pdev->dev,
- "GICv2m: MSI setup failed. Cannnot allocate IRQ\n");
- return -ENOSPC;
- }
+ if (desc->msi_attrib.is_msix) {
+ /**
+ * For MSIx:
+ * We allocate one irq at a time
+ */
+ avail = alloc_msi_irq(data, 1, &irq);
+ if (avail != 0) {
+ dev_err(&pdev->dev,
+ "GICv2m: MSI setup failed. Cannnot allocate IRQ\n");
+ return -ENOSPC;
+ }
- irq_set_chip_data(irq, chip);
- irq_set_msi_desc(irq, desc);
- irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
+ irq_set_chip_data(irq, chip);
+ irq_set_msi_desc(irq, desc);
+ irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
+ } else {
+ /**
+ * For MSI and Multi-MSI:
+ * All requested irqs are allocated and setup at
+ * once. Subsequent calls to this function would simply return
+ * success. This is to avoid having to implement a separate
+ * function for setting up multiple irqs.
+ */
+ BUG_ON(list_empty(&pdev->msi_list));
+ WARN_ON(!list_is_singular(&pdev->msi_list));
+
+ nvec = gicv2m_msi_get_vec_count(pdev, desc);
+ if (WARN_ON(nvec <= 0))
+ return nvec;
+
+ entry = list_first_entry(&pdev->msi_list,
+ struct msi_desc, list);
+
+ if ((nvec > 1) && (entry->msi_attrib.multiple))
+ return 0;
+
+ avail = alloc_msi_irq(data, nvec, &irq);
+ if (avail != 0) {
+ dev_err(&pdev->dev,
+ "GICv2m: Failed to allocate %d irqs.\n", nvec);
+ return avail;
+ }
+
+ if (nvec > 1) {
+ /* Set lowest of the new interrupts assigned
+ * to the PCI device
+ */
+ entry->nvec_used = nvec;
+ entry->msi_attrib.multiple = ilog2(
+ __roundup_pow_of_two(nvec));
+ }
+
+ for (i = 0; i < nvec; i++) {
+ irq_set_chip_data(irq+i, chip);
+ if (irq_set_msi_desc_off(irq, i, entry)) {
+ dev_err(&pdev->dev,
+ "GICv2m: Failed to set up MSI irq %d\n",
+ (irq+i));
+ return -EINVAL;
+ }
+
+ irq_set_irq_type((irq+i), IRQ_TYPE_EDGE_RISING);
+ }
+ }
addr = data->res.start + V2M_MSI_SETSPI_NS;
msg.address_hi = (u32)(addr >> 32);
--
1.9.3
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