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-rw-r--r--arch/mips/pci/pci-sb1250.c279
1 files changed, 279 insertions, 0 deletions
diff --git a/arch/mips/pci/pci-sb1250.c b/arch/mips/pci/pci-sb1250.c
new file mode 100644
index 0000000000..c3f82b2804
--- /dev/null
+++ b/arch/mips/pci/pci-sb1250.c
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2001,2002,2003 Broadcom Corporation
+ * Copyright (C) 2004 by Ralf Baechle (ralf@linux-mips.org)
+ */
+
+/*
+ * BCM1250-specific PCI support
+ *
+ * This module provides the glue between Linux's PCI subsystem
+ * and the hardware. We basically provide glue for accessing
+ * configuration space, and set up the translation for I/O
+ * space accesses.
+ *
+ * To access configuration space, we use ioremap. In the 32-bit
+ * kernel, this consumes either 4 or 8 page table pages, and 16MB of
+ * kernel mapped memory. Hopefully neither of these should be a huge
+ * problem.
+ */
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/console.h>
+#include <linux/tty.h>
+#include <linux/vt.h>
+
+#include <asm/io.h>
+
+#include <asm/sibyte/sb1250_defs.h>
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_scd.h>
+#include <asm/sibyte/board.h>
+
+/*
+ * Macros for calculating offsets into config space given a device
+ * structure or dev/fun/reg
+ */
+#define CFGOFFSET(bus, devfn, where) (((bus)<<16) + ((devfn)<<8) + (where))
+#define CFGADDR(bus, devfn, where) CFGOFFSET((bus)->number, (devfn), where)
+
+static void *cfg_space;
+
+#define PCI_BUS_ENABLED 1
+#define LDT_BUS_ENABLED 2
+#define PCI_DEVICE_MODE 4
+
+static int sb1250_bus_status;
+
+#define PCI_BRIDGE_DEVICE 0
+#define LDT_BRIDGE_DEVICE 1
+
+#ifdef CONFIG_SIBYTE_HAS_LDT
+/*
+ * HT's level-sensitive interrupts require EOI, which is generated
+ * through a 4MB memory-mapped region
+ */
+unsigned long ldt_eoi_space;
+#endif
+
+/*
+ * Read/write 32-bit values in config space.
+ */
+static inline u32 READCFG32(u32 addr)
+{
+ return *(u32 *) (cfg_space + (addr & ~3));
+}
+
+static inline void WRITECFG32(u32 addr, u32 data)
+{
+ *(u32 *) (cfg_space + (addr & ~3)) = data;
+}
+
+int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+ return dev->irq;
+}
+
+/* Do platform specific device initialization at pci_enable_device() time */
+int pcibios_plat_dev_init(struct pci_dev *dev)
+{
+ return 0;
+}
+
+/*
+ * Some checks before doing config cycles:
+ * In PCI Device Mode, hide everything on bus 0 except the LDT host
+ * bridge. Otherwise, access is controlled by bridge MasterEn bits.
+ */
+static int sb1250_pci_can_access(struct pci_bus *bus, int devfn)
+{
+ u32 devno;
+
+ if (!(sb1250_bus_status & (PCI_BUS_ENABLED | PCI_DEVICE_MODE)))
+ return 0;
+
+ if (bus->number == 0) {
+ devno = PCI_SLOT(devfn);
+ if (devno == LDT_BRIDGE_DEVICE)
+ return (sb1250_bus_status & LDT_BUS_ENABLED) != 0;
+ else if (sb1250_bus_status & PCI_DEVICE_MODE)
+ return 0;
+ else
+ return 1;
+ } else
+ return 1;
+}
+
+/*
+ * Read/write access functions for various sizes of values
+ * in config space. Return all 1's for disallowed accesses
+ * for a kludgy but adequate simulation of master aborts.
+ */
+
+static int sb1250_pcibios_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 * val)
+{
+ u32 data = 0;
+
+ if ((size == 2) && (where & 1))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+ else if ((size == 4) && (where & 3))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ if (sb1250_pci_can_access(bus, devfn))
+ data = READCFG32(CFGADDR(bus, devfn, where));
+ else
+ data = 0xFFFFFFFF;
+
+ if (size == 1)
+ *val = (data >> ((where & 3) << 3)) & 0xff;
+ else if (size == 2)
+ *val = (data >> ((where & 3) << 3)) & 0xffff;
+ else
+ *val = data;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int sb1250_pcibios_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val)
+{
+ u32 cfgaddr = CFGADDR(bus, devfn, where);
+ u32 data = 0;
+
+ if ((size == 2) && (where & 1))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+ else if ((size == 4) && (where & 3))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ if (!sb1250_pci_can_access(bus, devfn))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ data = READCFG32(cfgaddr);
+
+ if (size == 1)
+ data = (data & ~(0xff << ((where & 3) << 3))) |
+ (val << ((where & 3) << 3));
+ else if (size == 2)
+ data = (data & ~(0xffff << ((where & 3) << 3))) |
+ (val << ((where & 3) << 3));
+ else
+ data = val;
+
+ WRITECFG32(cfgaddr, data);
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops sb1250_pci_ops = {
+ .read = sb1250_pcibios_read,
+ .write = sb1250_pcibios_write,
+};
+
+static struct resource sb1250_mem_resource = {
+ .name = "SB1250 PCI MEM",
+ .start = 0x40000000UL,
+ .end = 0x5fffffffUL,
+ .flags = IORESOURCE_MEM,
+};
+
+static struct resource sb1250_io_resource = {
+ .name = "SB1250 PCI I/O",
+ .start = 0x00000000UL,
+ .end = 0x01ffffffUL,
+ .flags = IORESOURCE_IO,
+};
+
+struct pci_controller sb1250_controller = {
+ .pci_ops = &sb1250_pci_ops,
+ .mem_resource = &sb1250_mem_resource,
+ .io_resource = &sb1250_io_resource,
+};
+
+static int __init sb1250_pcibios_init(void)
+{
+ void __iomem *io_map_base;
+ uint32_t cmdreg;
+ uint64_t reg;
+
+ /* CFE will assign PCI resources */
+ pci_set_flags(PCI_PROBE_ONLY);
+
+ /* Avoid ISA compat ranges. */
+ PCIBIOS_MIN_IO = 0x00008000UL;
+ PCIBIOS_MIN_MEM = 0x01000000UL;
+
+ /* Set I/O resource limits. */
+ ioport_resource.end = 0x01ffffffUL; /* 32MB accessible by sb1250 */
+ iomem_resource.end = 0xffffffffUL; /* no HT support yet */
+
+ cfg_space =
+ ioremap(A_PHYS_LDTPCI_CFG_MATCH_BITS, 16 * 1024 * 1024);
+
+ /*
+ * See if the PCI bus has been configured by the firmware.
+ */
+ reg = __raw_readq(IOADDR(A_SCD_SYSTEM_CFG));
+ if (!(reg & M_SYS_PCI_HOST)) {
+ sb1250_bus_status |= PCI_DEVICE_MODE;
+ } else {
+ cmdreg =
+ READCFG32(CFGOFFSET
+ (0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0),
+ PCI_COMMAND));
+ if (!(cmdreg & PCI_COMMAND_MASTER)) {
+ printk
+ ("PCI: Skipping PCI probe. Bus is not initialized.\n");
+ iounmap(cfg_space);
+ return 0;
+ }
+ sb1250_bus_status |= PCI_BUS_ENABLED;
+ }
+
+ /*
+ * Establish mappings in KSEG2 (kernel virtual) to PCI I/O
+ * space. Use "match bytes" policy to make everything look
+ * little-endian. So, you need to also set
+ * CONFIG_SWAP_IO_SPACE, but this is the combination that
+ * works correctly with most of Linux's drivers.
+ * XXX ehs: Should this happen in PCI Device mode?
+ */
+ io_map_base = ioremap(A_PHYS_LDTPCI_IO_MATCH_BYTES, 1024 * 1024);
+ sb1250_controller.io_map_base = (unsigned long)io_map_base;
+ set_io_port_base((unsigned long)io_map_base);
+
+#ifdef CONFIG_SIBYTE_HAS_LDT
+ /*
+ * Also check the LDT bridge's enable, just in case we didn't
+ * initialize that one.
+ */
+
+ cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(LDT_BRIDGE_DEVICE, 0),
+ PCI_COMMAND));
+ if (cmdreg & PCI_COMMAND_MASTER) {
+ sb1250_bus_status |= LDT_BUS_ENABLED;
+
+ /*
+ * Need bits 23:16 to convey vector number. Note that
+ * this consumes 4MB of kernel-mapped memory
+ * (Kseg2/Kseg3) for 32-bit kernel.
+ */
+ ldt_eoi_space = (unsigned long)
+ ioremap(A_PHYS_LDT_SPECIAL_MATCH_BYTES,
+ 4 * 1024 * 1024);
+ }
+#endif
+
+ register_pci_controller(&sb1250_controller);
+
+#ifdef CONFIG_VGA_CONSOLE
+ console_lock();
+ do_take_over_console(&vga_con, 0, MAX_NR_CONSOLES - 1, 1);
+ console_unlock();
+#endif
+ return 0;
+}
+arch_initcall(sb1250_pcibios_init);