diff options
Diffstat (limited to 'arch/powerpc/platforms/pasemi/pci.c')
-rw-r--r-- | arch/powerpc/platforms/pasemi/pci.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pasemi/pci.c b/arch/powerpc/platforms/pasemi/pci.c new file mode 100644 index 0000000000..f27d314147 --- /dev/null +++ b/arch/powerpc/platforms/pasemi/pci.c @@ -0,0 +1,294 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2006 PA Semi, Inc + * + * Authors: Kip Walker, PA Semi + * Olof Johansson, PA Semi + * + * Maintained by: Olof Johansson <olof@lixom.net> + * + * Based on arch/powerpc/platforms/maple/pci.c + */ + + +#include <linux/kernel.h> +#include <linux/of_address.h> +#include <linux/pci.h> + +#include <asm/pci-bridge.h> +#include <asm/isa-bridge.h> +#include <asm/machdep.h> + +#include <asm/ppc-pci.h> + +#include "pasemi.h" + +#define PA_PXP_CFA(bus, devfn, off) (((bus) << 20) | ((devfn) << 12) | (off)) + +static inline int pa_pxp_offset_valid(u8 bus, u8 devfn, int offset) +{ + /* Device 0 Function 0 is special: It's config space spans function 1 as + * well, so allow larger offset. It's really a two-function device but the + * second function does not probe. + */ + if (bus == 0 && devfn == 0) + return offset < 8192; + else + return offset < 4096; +} + +static void volatile __iomem *pa_pxp_cfg_addr(struct pci_controller *hose, + u8 bus, u8 devfn, int offset) +{ + return hose->cfg_data + PA_PXP_CFA(bus, devfn, offset); +} + +static inline int is_root_port(int busno, int devfn) +{ + return ((busno == 0) && (PCI_FUNC(devfn) < 4) && + ((PCI_SLOT(devfn) == 16) || (PCI_SLOT(devfn) == 17))); +} + +static inline int is_5945_reg(int reg) +{ + return (((reg >= 0x18) && (reg < 0x34)) || + ((reg >= 0x158) && (reg < 0x178))); +} + +static int workaround_5945(struct pci_bus *bus, unsigned int devfn, + int offset, int len, u32 *val) +{ + struct pci_controller *hose; + void volatile __iomem *addr, *dummy; + int byte; + u32 tmp; + + if (!is_root_port(bus->number, devfn) || !is_5945_reg(offset)) + return 0; + + hose = pci_bus_to_host(bus); + + addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset & ~0x3); + byte = offset & 0x3; + + /* Workaround bug 5945: write 0 to a dummy register before reading, + * and write back what we read. We must read/write the full 32-bit + * contents so we need to shift and mask by hand. + */ + dummy = pa_pxp_cfg_addr(hose, bus->number, devfn, 0x10); + out_le32(dummy, 0); + tmp = in_le32(addr); + out_le32(addr, tmp); + + switch (len) { + case 1: + *val = (tmp >> (8*byte)) & 0xff; + break; + case 2: + if (byte == 0) + *val = tmp & 0xffff; + else + *val = (tmp >> 16) & 0xffff; + break; + default: + *val = tmp; + break; + } + + return 1; +} + +#ifdef CONFIG_PPC_PASEMI_NEMO +#define PXP_ERR_CFG_REG 0x4 +#define PXP_IGNORE_PCIE_ERRORS 0x800 +#define SB600_BUS 5 + +static void sb600_set_flag(int bus) +{ + static void __iomem *iob_mapbase = NULL; + struct resource res; + struct device_node *dn; + int err; + + if (iob_mapbase == NULL) { + dn = of_find_compatible_node(NULL, "isa", "pasemi,1682m-iob"); + if (!dn) { + pr_crit("NEMO SB600 missing iob node\n"); + return; + } + + err = of_address_to_resource(dn, 0, &res); + of_node_put(dn); + + if (err) { + pr_crit("NEMO SB600 missing resource\n"); + return; + } + + pr_info("NEMO SB600 IOB base %08llx\n",res.start); + + iob_mapbase = ioremap(res.start + 0x100, 0x94); + } + + if (iob_mapbase != NULL) { + if (bus == SB600_BUS) { + /* + * This is the SB600's bus, tell the PCI-e root port + * to allow non-zero devices to enumerate. + */ + out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) | PXP_IGNORE_PCIE_ERRORS); + } else { + /* + * Only scan device 0 on other busses + */ + out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) & ~PXP_IGNORE_PCIE_ERRORS); + } + } +} + +#else + +static void sb600_set_flag(int bus) +{ +} +#endif + +static int pa_pxp_read_config(struct pci_bus *bus, unsigned int devfn, + int offset, int len, u32 *val) +{ + struct pci_controller *hose; + void volatile __iomem *addr; + + hose = pci_bus_to_host(bus); + if (!hose) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (!pa_pxp_offset_valid(bus->number, devfn, offset)) + return PCIBIOS_BAD_REGISTER_NUMBER; + + if (workaround_5945(bus, devfn, offset, len, val)) + return PCIBIOS_SUCCESSFUL; + + addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset); + + sb600_set_flag(bus->number); + + /* + * Note: the caller has already checked that offset is + * suitably aligned and that len is 1, 2 or 4. + */ + switch (len) { + case 1: + *val = in_8(addr); + break; + case 2: + *val = in_le16(addr); + break; + default: + *val = in_le32(addr); + break; + } + + return PCIBIOS_SUCCESSFUL; +} + +static int pa_pxp_write_config(struct pci_bus *bus, unsigned int devfn, + int offset, int len, u32 val) +{ + struct pci_controller *hose; + void volatile __iomem *addr; + + hose = pci_bus_to_host(bus); + if (!hose) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (!pa_pxp_offset_valid(bus->number, devfn, offset)) + return PCIBIOS_BAD_REGISTER_NUMBER; + + addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset); + + sb600_set_flag(bus->number); + + /* + * Note: the caller has already checked that offset is + * suitably aligned and that len is 1, 2 or 4. + */ + switch (len) { + case 1: + out_8(addr, val); + break; + case 2: + out_le16(addr, val); + break; + default: + out_le32(addr, val); + break; + } + return PCIBIOS_SUCCESSFUL; +} + +static struct pci_ops pa_pxp_ops = { + .read = pa_pxp_read_config, + .write = pa_pxp_write_config, +}; + +static void __init setup_pa_pxp(struct pci_controller *hose) +{ + hose->ops = &pa_pxp_ops; + hose->cfg_data = ioremap(0xe0000000, 0x10000000); +} + +static int __init pas_add_bridge(struct device_node *dev) +{ + struct pci_controller *hose; + + pr_debug("Adding PCI host bridge %pOF\n", dev); + + hose = pcibios_alloc_controller(dev); + if (!hose) + return -ENOMEM; + + hose->first_busno = 0; + hose->last_busno = 0xff; + hose->controller_ops = pasemi_pci_controller_ops; + + setup_pa_pxp(hose); + + pr_info("Found PA-PXP PCI host bridge.\n"); + + /* Interpret the "ranges" property */ + pci_process_bridge_OF_ranges(hose, dev, 1); + + /* + * Scan for an isa bridge. This is needed to find the SB600 on the nemo + * and does nothing on machines without one. + */ + isa_bridge_find_early(hose); + + return 0; +} + +void __init pas_pci_init(void) +{ + struct device_node *np; + int res; + + pci_set_flags(PCI_SCAN_ALL_PCIE_DEVS); + + np = of_find_compatible_node(of_root, NULL, "pasemi,rootbus"); + if (np) { + res = pas_add_bridge(np); + of_node_put(np); + } +} + +void __iomem *__init pasemi_pci_getcfgaddr(struct pci_dev *dev, int offset) +{ + struct pci_controller *hose; + + hose = pci_bus_to_host(dev->bus); + + return (void __iomem *)pa_pxp_cfg_addr(hose, dev->bus->number, dev->devfn, offset); +} + +struct pci_controller_ops pasemi_pci_controller_ops; |