This patch extends FDT generation to generate PCI host DT node.
Of course, PCI host for Guest/VM is not useful at the moment
because it's mostly for PCI pass-through and we don't have
IOMMU and interrupt routing available for KVM RISC-V. In future,
we might be able to use PCI host for VirtIO PCI transport or
other software emulated PCI devices.
Signed-off-by: Anup Patel <anup.patel@xxxxxxx>
---
Makefile | 1 +
riscv/fdt.c | 3 +
riscv/include/kvm/kvm-arch.h | 2 +
riscv/pci.c | 109 +++++++++++++++++++++++++++++++++++
4 files changed, 115 insertions(+)
create mode 100644 riscv/pci.c
diff --git a/Makefile b/Makefile
index e4e1184..6920d7f 100644
--- a/Makefile
+++ b/Makefile
@@ -204,6 +204,7 @@ ifeq ($(ARCH),riscv)
OBJS += riscv/irq.o
OBJS += riscv/kvm.o
OBJS += riscv/kvm-cpu.o
+ OBJS += riscv/pci.o
OBJS += riscv/plic.o
ifeq ($(RISCV_XLEN),32)
CFLAGS += -mabi=ilp32d -march=rv32gc
diff --git a/riscv/fdt.c b/riscv/fdt.c
index 6527ef7..de15bfe 100644
--- a/riscv/fdt.c
+++ b/riscv/fdt.c
@@ -167,6 +167,9 @@ static int setup_fdt(struct kvm *kvm)
dev_hdr = device__next_dev(dev_hdr);
}
+ /* PCI host controller */
+ pci__generate_fdt_nodes(fdt);
+
_FDT(fdt_end_node(fdt));
if (fdt_stdout_path) {
diff --git a/riscv/include/kvm/kvm-arch.h b/riscv/include/kvm/kvm-arch.h
index d0be965..f090883 100644
--- a/riscv/include/kvm/kvm-arch.h
+++ b/riscv/include/kvm/kvm-arch.h
@@ -84,4 +84,6 @@ void plic__generate_irq_prop(void *fdt, u8 irq, enum irq_type irq_type);
void plic__irq_trig(struct kvm *kvm, int irq, int level, bool edge);
+void pci__generate_fdt_nodes(void *fdt);
+
#endif /* KVM__KVM_ARCH_H */
diff --git a/riscv/pci.c b/riscv/pci.c
new file mode 100644
index 0000000..604fd20
--- /dev/null
+++ b/riscv/pci.c
@@ -0,0 +1,109 @@
+#include "kvm/devices.h"
+#include "kvm/fdt.h"
+#include "kvm/kvm.h"
+#include "kvm/of_pci.h"
+#include "kvm/pci.h"
+#include "kvm/util.h"
+
+/*
+ * An entry in the interrupt-map table looks like:
+ * <pci unit address> <pci interrupt pin> <plic phandle> <plic interrupt>
+ */
+
+struct of_interrupt_map_entry {
+ struct of_pci_irq_mask pci_irq_mask;
+ u32 plic_phandle;
+ u32 plic_irq;
+} __attribute__((packed));
+
+void pci__generate_fdt_nodes(void *fdt)
+{
+ struct device_header *dev_hdr;
+ struct of_interrupt_map_entry irq_map[OF_PCI_IRQ_MAP_MAX];
+ unsigned nentries = 0;
+ /* Bus range */
+ u32 bus_range[] = { cpu_to_fdt32(0), cpu_to_fdt32(1), };
+ /* Configuration Space */
+ u64 cfg_reg_prop[] = { cpu_to_fdt64(KVM_PCI_CFG_AREA),
+ cpu_to_fdt64(RISCV_PCI_CFG_SIZE), };
+ /* Describe the memory ranges */
+ struct of_pci_ranges_entry ranges[] = {
+ {
+ .pci_addr = {
+ .hi = cpu_to_fdt32(of_pci_b_ss(OF_PCI_SS_IO)),
+ .mid = 0,
+ .lo = 0,
+ },
+ .cpu_addr = cpu_to_fdt64(KVM_IOPORT_AREA),
+ .length = cpu_to_fdt64(RISCV_IOPORT_SIZE),
+ },
+ {
+ .pci_addr = {
+ .hi = cpu_to_fdt32(of_pci_b_ss(OF_PCI_SS_M32)),
+ .mid = cpu_to_fdt32(KVM_PCI_MMIO_AREA >> 32),
+ .lo = cpu_to_fdt32(KVM_PCI_MMIO_AREA),
+ },
+ .cpu_addr = cpu_to_fdt64(KVM_PCI_MMIO_AREA),
+ .length = cpu_to_fdt64(RISCV_PCI_MMIO_SIZE),
+ },
+ };
+
+ /* Boilerplate PCI properties */
+ _FDT(fdt_begin_node(fdt, "pci"));
+ _FDT(fdt_property_string(fdt, "device_type", "pci"));
+ _FDT(fdt_property_cell(fdt, "#address-cells", 0x3));
+ _FDT(fdt_property_cell(fdt, "#size-cells", 0x2));
+ _FDT(fdt_property_cell(fdt, "#interrupt-cells", 0x1));
+ _FDT(fdt_property_string(fdt, "compatible", "pci-host-ecam-generic"));
+ _FDT(fdt_property(fdt, "dma-coherent", NULL, 0));
+
+ _FDT(fdt_property(fdt, "bus-range", bus_range, sizeof(bus_range)));
+ _FDT(fdt_property(fdt, "reg", &cfg_reg_prop, sizeof(cfg_reg_prop)));
+ _FDT(fdt_property(fdt, "ranges", ranges, sizeof(ranges)));
+
+ /* Generate the interrupt map ... */
+ dev_hdr = device__first_dev(DEVICE_BUS_PCI);
+ while (dev_hdr && nentries < ARRAY_SIZE(irq_map)) {
+ struct of_interrupt_map_entry *entry = &irq_map[nentries];
+ struct pci_device_header *pci_hdr = dev_hdr->data;
+ u8 dev_num = dev_hdr->dev_num;
+ u8 pin = pci_hdr->irq_pin;
+ u8 irq = pci_hdr->irq_line;
+
+ *entry = (struct of_interrupt_map_entry) {
+ .pci_irq_mask = {
+ .pci_addr = {
+ .hi = cpu_to_fdt32(of_pci_b_ddddd(dev_num)),
+ .mid = 0,
+ .lo = 0,
+ },
+ .pci_pin = cpu_to_fdt32(pin),
+ },
+ .plic_phandle = cpu_to_fdt32(PHANDLE_PLIC),
+ .plic_irq = cpu_to_fdt32(irq),
+ };
+
+ nentries++;
+ dev_hdr = device__next_dev(dev_hdr);
+ }
+
+ _FDT(fdt_property(fdt, "interrupt-map", irq_map,
+ sizeof(struct of_interrupt_map_entry) * nentries));
+
+ /* ... and the corresponding mask. */
+ if (nentries) {
+ struct of_pci_irq_mask irq_mask = {
+ .pci_addr = {
+ .hi = cpu_to_fdt32(of_pci_b_ddddd(-1)),
+ .mid = 0,
+ .lo = 0,
+ },
+ .pci_pin = cpu_to_fdt32(7),
+ };
+
+ _FDT(fdt_property(fdt, "interrupt-map-mask", &irq_mask,
+ sizeof(irq_mask)));
+ }
+
+ _FDT(fdt_end_node(fdt));
+}
--
2.25.1
