Add a simple ACPI based PCI host controller. This is done by providing a simple implementation for pci_acpi_scan_root(). The pci_mmcfg_list handling is done by the ACPI code, we keep a reference to the pci_mmcfg_region which is already mapped. Provide implementations of raw_pci_read and raw_pci_write based on the pci_mmcfg_list This is enabled only for ARM64 now. Signed-off-by: Jayachandran C <jchandra@xxxxxxxxxxxx> --- drivers/acpi/Kconfig | 8 ++ drivers/acpi/Makefile | 1 + drivers/acpi/pci_host_acpi.c | 186 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 195 insertions(+) create mode 100644 drivers/acpi/pci_host_acpi.c diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 25dbb76..dceb871 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -283,6 +283,14 @@ config ACPI_NUMA depends on (X86 || IA64) default y if IA64_GENERIC || IA64_SGI_SN2 +config ACPI_PCI_HOST_GENERIC + bool "Generic ACPI PCI host controller" + depends on ARM64 && ACPI + help + Say Y here if you want to support a simple generic ACPI PCI host + controller. + + config ACPI_CUSTOM_DSDT_FILE string "Custom DSDT Table file to include" default "" diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 0780ced..52eb38f 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -41,6 +41,7 @@ acpi-y += ec.o acpi-$(CONFIG_ACPI_DOCK) += dock.o acpi-y += pci_root.o pci_link.o pci_irq.o acpi-$(CONFIG_PCI_MMCONFIG) += pci_mcfg.o +acpi-$(CONFIG_ACPI_PCI_HOST_GENERIC) += pci_host_acpi.o acpi-y += acpi_lpss.o acpi_apd.o acpi-y += acpi_platform.o acpi-y += acpi_pnp.o diff --git a/drivers/acpi/pci_host_acpi.c b/drivers/acpi/pci_host_acpi.c new file mode 100644 index 0000000..9dbdd81 --- /dev/null +++ b/drivers/acpi/pci_host_acpi.c @@ -0,0 +1,186 @@ +/* + * Generic PCI host controller driver for ACPI based systems + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Copyright (c) 2015 Broadcom Corporation + * + * Based on drivers/pci/host/pci-host-generic.c + * Copyright (C) 2014 ARM Limited + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/acpi.h> +#include <linux/pci-acpi.h> +#include <linux/sfi_acpi.h> +#include <linux/slab.h> + +#define PREFIX "pci-host-acpi:" + +/* sysdata pointer is ->root_info */ +struct gen_acpi_root_info { + struct acpi_pci_root_info common; + struct pci_mmcfg_region *mcfg; + bool mcfg_added; +}; + +/* find mapping of a MCFG area */ +static void __iomem *gen_acpi_map_cfg_bus(struct pci_bus *bus, + unsigned int devfn, int where) +{ + struct gen_acpi_root_info *pci = bus->sysdata; + struct pci_mmcfg_region *mcfg = pci->mcfg; + + if (bus->number < mcfg->start_bus || bus->number > mcfg->end_bus) + return NULL; + + return mcfg->virt + + PCI_MMCFG_OFFSET(bus->number - mcfg->start_bus, devfn) + + where; +} + +static struct pci_ops gen_acpi_pci_ops = { + .map_bus = gen_acpi_map_cfg_bus, + .read = pci_generic_config_read, + .write = pci_generic_config_write, +}; + +/* Insert the ECFG area for a root bus */ +static int pci_acpi_root_init_info(struct acpi_pci_root_info *ci) +{ + struct gen_acpi_root_info *info; + struct acpi_pci_root *root = ci->root; + struct device *dev = &ci->bridge->dev; + int err; + + info = container_of(ci, struct gen_acpi_root_info, common); + err = pci_mmconfig_insert(dev, root->segment, root->secondary.start, + root->secondary.end, root->mcfg_addr); + if (err && err != -EEXIST) + return err; + + info->mcfg = pci_mmconfig_lookup(root->segment, root->secondary.start); + WARN_ON(info->mcfg == NULL); + info->mcfg_added = (err == -EEXIST); + return 0; +} + +static void pci_acpi_root_release_info(struct acpi_pci_root_info *ci) +{ + struct gen_acpi_root_info *info; + struct acpi_pci_root *root = ci->root; + + info = container_of(ci, struct gen_acpi_root_info, common); + if (info->mcfg_added) + pci_mmconfig_delete(root->segment, root->secondary.start, + root->secondary.end); + info->mcfg = NULL; +} + +static struct acpi_pci_root_ops pci_acpi_root_ops = { + .pci_ops = &gen_acpi_pci_ops, + .init_info = pci_acpi_root_init_info, + .release_info = pci_acpi_root_release_info, +}; + +struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) +{ + struct acpi_device *device = root->device; + struct gen_acpi_root_info *ri; + struct pci_bus *bus, *child; + + /* allocate acpi_info/sysdata */ + ri = devm_kzalloc(&device->dev, sizeof(*ri), GFP_KERNEL); + if (!ri) { + dev_err(&device->dev, + "pci_bus %04x:%02x: ignored (out of memory)\n", + root->segment, (int)root->secondary.start); + return NULL; + } + + bus = acpi_pci_root_create(root, &pci_acpi_root_ops, + &ri->common, ri); + if (!bus) { + dev_err(&device->dev, "Scanning rootbus failed"); + return NULL; + } + + pci_bus_size_bridges(bus); + pci_bus_assign_resources(bus); + list_for_each_entry(child, &bus->children, node) + pcie_bus_configure_settings(child); + + return bus; +} + +int raw_pci_read(unsigned int seg, unsigned int bus, + unsigned int devfn, int reg, int len, u32 *val) +{ + struct pci_mmcfg_region *mcfg; + void __iomem *addr; + int err = -EINVAL; + + rcu_read_lock(); + mcfg = pci_mmconfig_lookup(seg, bus); + if (!mcfg || !mcfg->virt) + goto err; + + addr = mcfg->virt + PCI_MMCFG_OFFSET(bus, devfn); + switch (len) { + case 1: + *val = readb(addr + reg); + break; + case 2: + *val = readw(addr + reg); + break; + case 4: + *val = readl(addr + reg); + break; + } + err = 0; +err: + rcu_read_unlock(); + return err; +} + +int raw_pci_write(unsigned int seg, unsigned int bus, + unsigned int devfn, int reg, int len, u32 val) +{ + struct pci_mmcfg_region *mcfg; + void __iomem *addr; + int err = -EINVAL; + + rcu_read_lock(); + mcfg = pci_mmconfig_lookup(seg, bus); + if (!mcfg || !mcfg->virt) + goto err; + + addr = mcfg->virt + PCI_MMCFG_OFFSET(bus, devfn); + switch (len) { + case 1: + writeb(val, addr + reg); + break; + case 2: + writew(val, addr + reg); + break; + case 4: + writel(val, addr + reg); + break; + } + err = 0; +err: + rcu_read_unlock(); + return err; +} -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
