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-rw-r--r--arch/sparc/kernel/leon_pci.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/sparc/kernel/leon_pci.c b/arch/sparc/kernel/leon_pci.c
new file mode 100644
index 000000000..8de6646e9
--- /dev/null
+++ b/arch/sparc/kernel/leon_pci.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * leon_pci.c: LEON Host PCI support
+ *
+ * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
+ *
+ * Code is partially derived from pcic.c
+ */
+
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/export.h>
+#include <asm/leon.h>
+#include <asm/leon_pci.h>
+
+/* The LEON architecture does not rely on a BIOS or bootloader to setup
+ * PCI for us. The Linux generic routines are used to setup resources,
+ * reset values of configuration-space register settings are preserved.
+ *
+ * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
+ * accessed through a Window which is translated to low 64KB in PCI space, the
+ * first 4KB is not used so 60KB is available.
+ */
+void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
+{
+ LIST_HEAD(resources);
+ struct pci_bus *root_bus;
+ struct pci_host_bridge *bridge;
+ int ret;
+
+ bridge = pci_alloc_host_bridge(0);
+ if (!bridge)
+ return;
+
+ pci_add_resource_offset(&resources, &info->io_space,
+ info->io_space.start - 0x1000);
+ pci_add_resource(&resources, &info->mem_space);
+ info->busn.flags = IORESOURCE_BUS;
+ pci_add_resource(&resources, &info->busn);
+
+ list_splice_init(&resources, &bridge->windows);
+ bridge->dev.parent = &ofdev->dev;
+ bridge->sysdata = info;
+ bridge->busnr = 0;
+ bridge->ops = info->ops;
+ bridge->swizzle_irq = pci_common_swizzle;
+ bridge->map_irq = info->map_irq;
+
+ ret = pci_scan_root_bus_bridge(bridge);
+ if (ret) {
+ pci_free_host_bridge(bridge);
+ return;
+ }
+
+ root_bus = bridge->bus;
+
+ /* Assign devices with resources */
+ pci_assign_unassigned_resources();
+ pci_bus_add_devices(root_bus);
+}
+
+int pcibios_enable_device(struct pci_dev *dev, int mask)
+{
+ struct resource *res;
+ u16 cmd, oldcmd;
+ int i;
+
+ pci_read_config_word(dev, PCI_COMMAND, &cmd);
+ oldcmd = cmd;
+
+ pci_dev_for_each_resource(dev, res, i) {
+ /* Only set up the requested stuff */
+ if (!(mask & (1<<i)))
+ continue;
+
+ if (res->flags & IORESOURCE_IO)
+ cmd |= PCI_COMMAND_IO;
+ if (res->flags & IORESOURCE_MEM)
+ cmd |= PCI_COMMAND_MEMORY;
+ }
+
+ if (cmd != oldcmd) {
+ pci_info(dev, "enabling device (%04x -> %04x)\n", oldcmd, cmd);
+ pci_write_config_word(dev, PCI_COMMAND, cmd);
+ }
+ return 0;
+}