Read the memory ranges behind the Broadcom CNB20LE host bridge out of the hardware. This allows PCI hotplugging to work, since we know which memory range to allocate PCI BAR's from. The x86 PCI code automatically prefers the ACPI _CRS information when it is available. In that case, this information is not used. Signed-off-by: Ira W. Snyder <iws@xxxxxxxxxxxxxxxx> --- v1 -> v2: * use dev_info() to print host bridge window information * hide the code behind a config option * improve printed strings Thanks for the review of the last version of this patch! Ira arch/x86/Kconfig | 8 +++ arch/x86/pci/Makefile | 2 + arch/x86/pci/broadcom_bus.c | 101 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 111 insertions(+), 0 deletions(-) create mode 100644 arch/x86/pci/broadcom_bus.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0eacb1f..ea10aac 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1931,6 +1931,14 @@ config PCI_MMCONFIG bool "Support mmconfig PCI config space access" depends on X86_64 && PCI && ACPI +config PCI_CNB20LE_QUIRK + bool "Read CNB20LE Host Bridge Windows" + depends on PCI + help + Read the PCI windows out of the CNB20LE host bridge. This allows + PCI hotplug to work on systems with the CNB20LE chipset which do + not have ACPI. + config DMAR bool "Support for DMA Remapping Devices (EXPERIMENTAL)" depends on PCI_MSI && ACPI && EXPERIMENTAL diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile index b110d97..a0207a7 100644 --- a/arch/x86/pci/Makefile +++ b/arch/x86/pci/Makefile @@ -18,6 +18,8 @@ obj-$(CONFIG_X86_MRST) += mrst.o obj-y += common.o early.o obj-y += amd_bus.o bus_numa.o +obj-$(CONFIG_PCI_CNB20LE_QUIRK) += broadcom_bus.o + ifeq ($(CONFIG_PCI_DEBUG),y) EXTRA_CFLAGS += -DDEBUG endif diff --git a/arch/x86/pci/broadcom_bus.c b/arch/x86/pci/broadcom_bus.c new file mode 100644 index 0000000..0846a5b --- /dev/null +++ b/arch/x86/pci/broadcom_bus.c @@ -0,0 +1,101 @@ +/* + * Read address ranges from a Broadcom CNB20LE Host Bridge + * + * Copyright (c) 2010 Ira W. Snyder <iws@xxxxxxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/delay.h> +#include <linux/dmi.h> +#include <linux/pci.h> +#include <linux/init.h> +#include <asm/pci_x86.h> + +#include "bus_numa.h" + +static void __devinit cnb20le_res(struct pci_dev *dev) +{ + struct pci_root_info *info; + struct resource res; + u16 word1, word2; + u8 fbus, lbus; + int i; + + /* + * The x86_pci_root_bus_res_quirks() function already refuses to use + * this information if ACPI _CRS was used. Therefore, we don't bother + * checking if ACPI is enabled, and just generate the information + * for both the ACPI _CRS and no ACPI cases. + */ + + info = &pci_root_info[pci_root_num]; + pci_root_num++; + + /* read the PCI bus numbers */ + pci_read_config_byte(dev, 0x44, &fbus); + pci_read_config_byte(dev, 0x45, &lbus); + info->bus_min = fbus; + info->bus_max = lbus; + + /* + * Add the legacy IDE ports on bus 0 + * + * These do not exist anywhere in the bridge registers, AFAICT. I do + * not have the datasheet, so this is the best I can do. + */ + if (fbus == 0) { + update_res(info, 0x01f0, 0x01f7, IORESOURCE_IO, 0); + update_res(info, 0x03f6, 0x03f6, IORESOURCE_IO, 0); + update_res(info, 0x0170, 0x0177, IORESOURCE_IO, 0); + update_res(info, 0x0376, 0x0376, IORESOURCE_IO, 0); + update_res(info, 0xffa0, 0xffaf, IORESOURCE_IO, 0); + } + + /* read the non-prefetchable memory window */ + pci_read_config_word(dev, 0xc0, &word1); + pci_read_config_word(dev, 0xc2, &word2); + if (word1 != word2) { + res.start = (word1 << 16) | 0x0000; + res.end = (word2 << 16) | 0xffff; + res.flags = IORESOURCE_MEM; + update_res(info, res.start, res.end, res.flags, 0); + } + + /* read the prefetchable memory window */ + pci_read_config_word(dev, 0xc4, &word1); + pci_read_config_word(dev, 0xc6, &word2); + if (word1 != word2) { + res.start = (word1 << 16) | 0x0000; + res.end = (word2 << 16) | 0xffff; + res.flags = IORESOURCE_MEM | IORESOURCE_PREFETCH; + update_res(info, res.start, res.end, res.flags, 0); + } + + /* read the IO port window */ + pci_read_config_word(dev, 0xd0, &word1); + pci_read_config_word(dev, 0xd2, &word2); + if (word1 != word2) { + res.start = word1; + res.end = word2; + res.flags = IORESOURCE_IO; + update_res(info, res.start, res.end, res.flags, 0); + } + + /* print information about this host bridge */ + res.start = fbus; + res.end = lbus; + res.flags = IORESOURCE_BUS; + dev_info(&dev->dev, "CNB20LE PCI Host Bridge (domain %04x %pR)\n", + pci_domain_nr(dev->bus), &res); + + for (i = 0; i < info->res_num; i++) + dev_info(&dev->dev, "host bridge window %pR\n", &info->res[i]); +} + +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_LE, + cnb20le_res); + -- 1.5.4.3 -- 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