From 5dde383e2ef5e22fe7db689dc38c1aabfb801449 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Mon, 9 Jul 2012 13:38:41 -0600 Subject: PCI: allow P2P bridge windows starting at PCI bus address zero cd81e1ea1a4c added checks that prevent us from using P2P bridge windows that start at PCI bus address zero. The reason was to "prevent us from overwriting resources that are unassigned." But generic code should allow address zero in both BARs and bridge windows, so I think that commit was a mistake. Windows at bus address zero are legal and likely to exist on machines with an offset between bus addresses and CPU addresses. For example, in the following hypothetical scenario, the bridge at 00:01.0 has a window at bus address zero and the device at 01:00.0 has a BAR at bus address zero, and I think both are perfectly valid: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [mem 0x100000000-0x1ffffffff] (bus address [0x00000000-0xffffffff]) pci 0000:00:01.0: PCI bridge to [bus 01] pci 0000:00:01.0: bridge window [mem 0x100000000-0x100ffffff] pci 0000:01:00.0: reg 10: [mem 0x100000000-0x100ffffff] Acked-by: Yinghai Lu Signed-off-by: Bjorn Helgaas --- drivers/pci/probe.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 658ac977cb56..9c5d2a992999 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -287,7 +287,7 @@ static void __devinit pci_read_bridge_io(struct pci_bus *child) limit |= (io_limit_hi << 16); } - if (base && base <= limit) { + if (base <= limit) { res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO; res2.flags = res->flags; region.start = base; @@ -314,7 +314,7 @@ static void __devinit pci_read_bridge_mmio(struct pci_bus *child) pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo); base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16; limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16; - if (base && base <= limit) { + if (base <= limit) { res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM; region.start = base; region.end = limit + 0xfffff; @@ -360,7 +360,7 @@ static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child) #endif } } - if (base && base <= limit) { + if (base <= limit) { res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH; if (res->flags & PCI_PREF_RANGE_TYPE_64) -- cgit v1.2.3-55-g7522 From 2b28ae1912e5ce5bb0527e352ae6ff04e76183d1 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Mon, 9 Jul 2012 13:38:57 -0600 Subject: PCI: reimplement P2P bridge 1K I/O windows (Intel P64H2) 9d265124d051 and 15a260d53f7c added quirks for P2P bridges that support I/O windows that start/end at 1K boundaries, not just the 4K boundaries defined by the PCI spec. For details, see the IOBL_ADR register and the EN1K bit in the CNF register in the Intel 82870P2 (P64H2). These quirks complicate the code that reads P2P bridge windows (pci_read_bridge_io() and pci_cfg_fake_ranges()) because the bridge I/O resource is updated in the HEADER quirk, in pci_read_bridge_io(), in pci_setup_bridge(), and again in the FINAL quirk. This is confusing and makes it impossible to reassign the bridge windows after FINAL quirks are run. This patch adds support for 1K windows in the generic paths, so the HEADER quirk only has to enable this support. The FINAL quirk, which used to undo damage done by pci_setup_bridge(), is no longer needed. This removes "if (!res->start) res->start = ..." from pci_read_bridge_io(); that was part of 9d265124d051 to avoid overwriting the resource filled in by the quirk. Since pci_read_bridge_io() itself now knows about granularity, the quirk no longer updates the resource and this test is no longer needed. Signed-off-by: Bjorn Helgaas --- drivers/pci/probe.c | 25 ++++++++++++++----------- drivers/pci/quirks.c | 39 +-------------------------------------- drivers/pci/setup-bus.c | 11 +++++++++-- include/linux/pci.h | 1 + include/linux/pci_regs.h | 3 ++- 5 files changed, 27 insertions(+), 52 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 9c5d2a992999..ef24cf765b2f 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -269,15 +269,23 @@ static void __devinit pci_read_bridge_io(struct pci_bus *child) { struct pci_dev *dev = child->self; u8 io_base_lo, io_limit_lo; - unsigned long base, limit; + unsigned long io_mask, io_granularity, base, limit; struct pci_bus_region region; - struct resource *res, res2; + struct resource *res; + + io_mask = PCI_IO_RANGE_MASK; + io_granularity = 0x1000; + if (dev->io_window_1k) { + /* Support 1K I/O space granularity */ + io_mask = PCI_IO_1K_RANGE_MASK; + io_granularity = 0x400; + } res = child->resource[0]; pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo); pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo); - base = (io_base_lo & PCI_IO_RANGE_MASK) << 8; - limit = (io_limit_lo & PCI_IO_RANGE_MASK) << 8; + base = (io_base_lo & io_mask) << 8; + limit = (io_limit_lo & io_mask) << 8; if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) { u16 io_base_hi, io_limit_hi; @@ -289,14 +297,9 @@ static void __devinit pci_read_bridge_io(struct pci_bus *child) if (base <= limit) { res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO; - res2.flags = res->flags; region.start = base; - region.end = limit + 0xfff; - pcibios_bus_to_resource(dev, &res2, ®ion); - if (!res->start) - res->start = res2.start; - if (!res->end) - res->end = res2.end; + region.end = limit + io_granularity - 1; + pcibios_bus_to_resource(dev, res, ®ion); dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res); } } diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 2a7521677541..356846bd7ffb 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -1938,53 +1938,16 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NCR, PCI_DEVICE_ID_NCR_53C810, fixup_rev1 static void __devinit quirk_p64h2_1k_io(struct pci_dev *dev) { u16 en1k; - u8 io_base_lo, io_limit_lo; - unsigned long base, limit; - struct resource *res = dev->resource + PCI_BRIDGE_RESOURCES; pci_read_config_word(dev, 0x40, &en1k); if (en1k & 0x200) { dev_info(&dev->dev, "Enable I/O Space to 1KB granularity\n"); - - pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo); - pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo); - base = (io_base_lo & (PCI_IO_RANGE_MASK | 0x0c)) << 8; - limit = (io_limit_lo & (PCI_IO_RANGE_MASK | 0x0c)) << 8; - - if (base <= limit) { - res->start = base; - res->end = limit + 0x3ff; - } + dev->io_window_1k = 1; } } DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x1460, quirk_p64h2_1k_io); -/* Fix the IOBL_ADR for 1k I/O space granularity on the Intel P64H2 - * The IOBL_ADR gets re-written to 4k boundaries in pci_setup_bridge() - * in drivers/pci/setup-bus.c - */ -static void __devinit quirk_p64h2_1k_io_fix_iobl(struct pci_dev *dev) -{ - u16 en1k, iobl_adr, iobl_adr_1k; - struct resource *res = dev->resource + PCI_BRIDGE_RESOURCES; - - pci_read_config_word(dev, 0x40, &en1k); - - if (en1k & 0x200) { - pci_read_config_word(dev, PCI_IO_BASE, &iobl_adr); - - iobl_adr_1k = iobl_adr | (res->start >> 8) | (res->end & 0xfc00); - - if (iobl_adr != iobl_adr_1k) { - dev_info(&dev->dev, "Fixing P64H2 IOBL_ADR from 0x%x to 0x%x for 1KB granularity\n", - iobl_adr,iobl_adr_1k); - pci_write_config_word(dev, PCI_IO_BASE, iobl_adr_1k); - } - } -} -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x1460, quirk_p64h2_1k_io_fix_iobl); - /* Under some circumstances, AER is not linked with extended capabilities. * Force it to be linked by setting the corresponding control bit in the * config space. diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 8fa2d4be88de..dad5425f1f09 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -469,16 +469,23 @@ static void pci_setup_bridge_io(struct pci_bus *bus) struct pci_dev *bridge = bus->self; struct resource *res; struct pci_bus_region region; + unsigned long io_mask; + u8 io_base_lo, io_limit_lo; u32 l, io_upper16; + io_mask = PCI_IO_RANGE_MASK; + if (bridge->io_window_1k) + io_mask = PCI_IO_1K_RANGE_MASK; + /* Set up the top and bottom of the PCI I/O segment for this bus. */ res = bus->resource[0]; pcibios_resource_to_bus(bridge, ®ion, res); if (res->flags & IORESOURCE_IO) { pci_read_config_dword(bridge, PCI_IO_BASE, &l); l &= 0xffff0000; - l |= (region.start >> 8) & 0x00f0; - l |= region.end & 0xf000; + io_base_lo = (region.start >> 8) & io_mask; + io_limit_lo = (region.end >> 8) & io_mask; + l |= ((u32) io_limit_lo << 8) | io_base_lo; /* Set up upper 16 bits of I/O base/limit. */ io_upper16 = (region.end & 0xffff0000) | (region.start >> 16); dev_info(&bridge->dev, " bridge window %pR\n", res); diff --git a/include/linux/pci.h b/include/linux/pci.h index d8c379dba6ad..89b46fd245c6 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -324,6 +324,7 @@ struct pci_dev { unsigned int is_hotplug_bridge:1; unsigned int __aer_firmware_first_valid:1; unsigned int __aer_firmware_first:1; + unsigned int io_window_1k:1; /* Intel P2P bridge 1K I/O windows */ pci_dev_flags_t dev_flags; atomic_t enable_cnt; /* pci_enable_device has been called */ diff --git a/include/linux/pci_regs.h b/include/linux/pci_regs.h index 4b608f543412..88c9ea56e252 100644 --- a/include/linux/pci_regs.h +++ b/include/linux/pci_regs.h @@ -125,7 +125,8 @@ #define PCI_IO_RANGE_TYPE_MASK 0x0fUL /* I/O bridging type */ #define PCI_IO_RANGE_TYPE_16 0x00 #define PCI_IO_RANGE_TYPE_32 0x01 -#define PCI_IO_RANGE_MASK (~0x0fUL) +#define PCI_IO_RANGE_MASK (~0x0fUL) /* Standard 4K I/O windows */ +#define PCI_IO_1K_RANGE_MASK (~0x03UL) /* Intel 1K I/O windows */ #define PCI_SEC_STATUS 0x1e /* Secondary status register, only bit 14 used */ #define PCI_MEMORY_BASE 0x20 /* Memory range behind */ #define PCI_MEMORY_LIMIT 0x22 -- cgit v1.2.3-55-g7522 From fd591341102ba5eb9e517d3889e7566fa45e021e Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Mon, 9 Jul 2012 19:55:29 -0600 Subject: PCI: support sizing P2P bridge I/O windows with 1K granularity Some bridges support I/O windows with 1K alignment, not just the 4K alignment defined by the PCI spec. For example, see the IOBL_ADR register and the EN1K bit in the CNF register in the Intel 82870P2 (P64H2). This patch adds support for sizing the window in 1K increments based on the requirements of downstream devices. [bhelgaas: changelog, comment] Signed-off-by: Yinghai Lu Signed-off-by: Bjorn Helgaas --- drivers/pci/setup-bus.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index dad5425f1f09..eb0293e23e48 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -706,7 +706,7 @@ static resource_size_t calculate_memsize(resource_size_t size, * @realloc_head : track the additional io window on this list * * Sizing the IO windows of the PCI-PCI bridge is trivial, - * since these windows have 4K granularity and the IO ranges + * since these windows have 1K or 4K granularity and the IO ranges * of non-bridge PCI devices are limited to 256 bytes. * We must be careful with the ISA aliasing though. */ @@ -717,10 +717,17 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO); unsigned long size = 0, size0 = 0, size1 = 0; resource_size_t children_add_size = 0; + resource_size_t min_align = 4096, align; if (!b_res) return; + /* + * Per spec, I/O windows are 4K-aligned, but some bridges have an + * extension to support 1K alignment. + */ + if (bus->self->io_window_1k) + min_align = 1024; list_for_each_entry(dev, &bus->devices, bus_list) { int i; @@ -738,17 +745,25 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, else size1 += r_size; + align = pci_resource_alignment(dev, r); + if (align > min_align) + min_align = align; + if (realloc_head) children_add_size += get_res_add_size(realloc_head, r); } } + + if (min_align > 4096) + min_align = 4096; + size0 = calculate_iosize(size, min_size, size1, - resource_size(b_res), 4096); + resource_size(b_res), min_align); if (children_add_size > add_size) add_size = children_add_size; size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 : calculate_iosize(size, min_size, add_size + size1, - resource_size(b_res), 4096); + resource_size(b_res), min_align); if (!size0 && !size1) { if (b_res->start || b_res->end) dev_info(&bus->self->dev, "disabling bridge window " @@ -757,12 +772,13 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, b_res->flags = 0; return; } - /* Alignment of the IO window is always 4K */ - b_res->start = 4096; + + b_res->start = min_align; b_res->end = b_res->start + size0 - 1; b_res->flags |= IORESOURCE_STARTALIGN; if (size1 > size0 && realloc_head) { - add_to_list(realloc_head, bus->self, b_res, size1-size0, 4096); + add_to_list(realloc_head, bus->self, b_res, size1-size0, + min_align); dev_printk(KERN_DEBUG, &bus->self->dev, "bridge window " "%pR to [bus %02x-%02x] add_size %lx\n", b_res, bus->secondary, bus->subordinate, size1-size0); -- cgit v1.2.3-55-g7522