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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/m68k/coldfire/pci.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/m68k/coldfire/pci.c')
-rw-r--r--arch/m68k/coldfire/pci.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/arch/m68k/coldfire/pci.c b/arch/m68k/coldfire/pci.c
new file mode 100644
index 0000000000..ceb5775b8d
--- /dev/null
+++ b/arch/m68k/coldfire/pci.c
@@ -0,0 +1,259 @@
+/*
+ * pci.c -- PCI bus support for ColdFire processors
+ *
+ * (C) Copyright 2012, Greg Ungerer <gerg@uclinux.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <asm/coldfire.h>
+#include <asm/mcfsim.h>
+#include <asm/m54xxpci.h>
+
+/*
+ * Memory and IO mappings. We use a 1:1 mapping for local host memory to
+ * PCI bus memory (no reason not to really). IO space is mapped in its own
+ * separate address region. The device configuration space is mapped over
+ * the IO map space when we enable it in the PCICAR register.
+ */
+static struct pci_bus *rootbus;
+static unsigned long iospace;
+
+/*
+ * We need to be careful probing on bus 0 (directly connected to host
+ * bridge). We should only access the well defined possible devices in
+ * use, ignore aliases and the like.
+ */
+static unsigned char mcf_host_slot2sid[32] = {
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 1, 2, 0, 3, 4, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+};
+
+static unsigned char mcf_host_irq[] = {
+ 0, 69, 69, 71, 71,
+};
+
+/*
+ * Configuration space access functions. Configuration space access is
+ * through the IO mapping window, enabling it via the PCICAR register.
+ */
+static unsigned long mcf_mk_pcicar(int bus, unsigned int devfn, int where)
+{
+ return (bus << PCICAR_BUSN) | (devfn << PCICAR_DEVFNN) | (where & 0xfc);
+}
+
+static int mcf_pci_readconfig(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *value)
+{
+ unsigned long addr;
+
+ *value = 0xffffffff;
+
+ if (bus->number == 0) {
+ if (mcf_host_slot2sid[PCI_SLOT(devfn)] == 0)
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ addr = mcf_mk_pcicar(bus->number, devfn, where);
+ __raw_writel(PCICAR_E | addr, PCICAR);
+ __raw_readl(PCICAR);
+ addr = iospace + (where & 0x3);
+
+ switch (size) {
+ case 1:
+ *value = __raw_readb(addr);
+ break;
+ case 2:
+ *value = le16_to_cpu(__raw_readw(addr));
+ break;
+ default:
+ *value = le32_to_cpu(__raw_readl(addr));
+ break;
+ }
+
+ __raw_writel(0, PCICAR);
+ __raw_readl(PCICAR);
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int mcf_pci_writeconfig(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 value)
+{
+ unsigned long addr;
+
+ if (bus->number == 0) {
+ if (mcf_host_slot2sid[PCI_SLOT(devfn)] == 0)
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ addr = mcf_mk_pcicar(bus->number, devfn, where);
+ __raw_writel(PCICAR_E | addr, PCICAR);
+ __raw_readl(PCICAR);
+ addr = iospace + (where & 0x3);
+
+ switch (size) {
+ case 1:
+ __raw_writeb(value, addr);
+ break;
+ case 2:
+ __raw_writew(cpu_to_le16(value), addr);
+ break;
+ default:
+ __raw_writel(cpu_to_le32(value), addr);
+ break;
+ }
+
+ __raw_writel(0, PCICAR);
+ __raw_readl(PCICAR);
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops mcf_pci_ops = {
+ .read = mcf_pci_readconfig,
+ .write = mcf_pci_writeconfig,
+};
+
+/*
+ * Initialize the PCI bus registers, and scan the bus.
+ */
+static struct resource mcf_pci_mem = {
+ .name = "PCI Memory space",
+ .start = PCI_MEM_PA,
+ .end = PCI_MEM_PA + PCI_MEM_SIZE - 1,
+ .flags = IORESOURCE_MEM,
+};
+
+static struct resource mcf_pci_io = {
+ .name = "PCI IO space",
+ .start = 0x400,
+ .end = 0x10000 - 1,
+ .flags = IORESOURCE_IO,
+};
+
+static struct resource busn_resource = {
+ .name = "PCI busn",
+ .start = 0,
+ .end = 255,
+ .flags = IORESOURCE_BUS,
+};
+
+/*
+ * Interrupt mapping and setting.
+ */
+static int mcf_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+ int sid;
+
+ sid = mcf_host_slot2sid[slot];
+ if (sid)
+ return mcf_host_irq[sid];
+ return 0;
+}
+
+static int __init mcf_pci_init(void)
+{
+ struct pci_host_bridge *bridge;
+ int ret;
+
+ bridge = pci_alloc_host_bridge(0);
+ if (!bridge)
+ return -ENOMEM;
+
+ pr_info("ColdFire: PCI bus initialization...\n");
+
+ /* Reset the external PCI bus */
+ __raw_writel(PCIGSCR_RESET, PCIGSCR);
+ __raw_writel(0, PCITCR);
+
+ request_resource(&iomem_resource, &mcf_pci_mem);
+ request_resource(&iomem_resource, &mcf_pci_io);
+
+ /* Configure PCI arbiter */
+ __raw_writel(PACR_INTMPRI | PACR_INTMINTE | PACR_EXTMPRI(0x1f) |
+ PACR_EXTMINTE(0x1f), PACR);
+
+ /* Set required multi-function pins for PCI bus use */
+ __raw_writew(0x3ff, MCFGPIO_PAR_PCIBG);
+ __raw_writew(0x3ff, MCFGPIO_PAR_PCIBR);
+
+ /* Set up config space for local host bus controller */
+ __raw_writel(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
+ PCI_COMMAND_INVALIDATE, PCISCR);
+ __raw_writel(PCICR1_LT(32) | PCICR1_CL(8), PCICR1);
+ __raw_writel(0, PCICR2);
+
+ /*
+ * Set up the initiator windows for memory and IO mapping.
+ * These give the CPU bus access onto the PCI bus. One for each of
+ * PCI memory and IO address spaces.
+ */
+ __raw_writel(WXBTAR(PCI_MEM_PA, PCI_MEM_BA, PCI_MEM_SIZE),
+ PCIIW0BTAR);
+ __raw_writel(WXBTAR(PCI_IO_PA, PCI_IO_BA, PCI_IO_SIZE),
+ PCIIW1BTAR);
+ __raw_writel(PCIIWCR_W0_MEM /*| PCIIWCR_W0_MRDL*/ | PCIIWCR_W0_E |
+ PCIIWCR_W1_IO | PCIIWCR_W1_E, PCIIWCR);
+
+ /*
+ * Set up the target windows for access from the PCI bus back to the
+ * CPU bus. All we need is access to system RAM (for mastering).
+ */
+ __raw_writel(CONFIG_RAMBASE, PCIBAR1);
+ __raw_writel(CONFIG_RAMBASE | PCITBATR1_E, PCITBATR1);
+
+ /* Keep a virtual mapping to IO/config space active */
+ iospace = (unsigned long) ioremap(PCI_IO_PA, PCI_IO_SIZE);
+ if (iospace == 0) {
+ pci_free_host_bridge(bridge);
+ return -ENODEV;
+ }
+ pr_info("Coldfire: PCI IO/config window mapped to 0x%x\n",
+ (u32) iospace);
+
+ /* Turn of PCI reset, and wait for devices to settle */
+ __raw_writel(0, PCIGSCR);
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(msecs_to_jiffies(200));
+
+
+ pci_add_resource(&bridge->windows, &ioport_resource);
+ pci_add_resource(&bridge->windows, &iomem_resource);
+ pci_add_resource(&bridge->windows, &busn_resource);
+ bridge->dev.parent = NULL;
+ bridge->sysdata = NULL;
+ bridge->busnr = 0;
+ bridge->ops = &mcf_pci_ops;
+ bridge->swizzle_irq = pci_common_swizzle;
+ bridge->map_irq = mcf_pci_map_irq;
+
+ ret = pci_scan_root_bus_bridge(bridge);
+ if (ret) {
+ pci_free_host_bridge(bridge);
+ return ret;
+ }
+
+ rootbus = bridge->bus;
+
+ rootbus->resource[0] = &mcf_pci_io;
+ rootbus->resource[1] = &mcf_pci_mem;
+
+ pci_bus_size_bridges(rootbus);
+ pci_bus_assign_resources(rootbus);
+ pci_bus_add_devices(rootbus);
+ return 0;
+}
+
+subsys_initcall(mcf_pci_init);