From 2ed6dc34f9ed39bb8e4c81ea1056f0ba56315841 Mon Sep 17 00:00:00 2001 From: Shannon Nelson Date: Tue, 16 Oct 2007 01:27:42 -0700 Subject: [PATCH] I/OAT: Add DCA services Add code to connect to the DCA driver and provide cpu tags for use by drivers that would like to use Direct Cache Access hints. [Adrian Bunk] Several Kconfig cleanup items [Andrew Morten, Chris Leech] Fix for using cpu_physical_id() even when built for uni-processor Signed-off-by: Shannon Nelson Acked-by: David S. Miller Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/dca/Kconfig | 6 +- drivers/dma/Kconfig | 68 +++++---- drivers/dma/Makefile | 2 +- drivers/dma/ioat.c | 17 ++- drivers/dma/ioat_dca.c | 263 ++++++++++++++++++++++++++++++++ drivers/dma/ioatdma.h | 3 + include/asm-x86/cpufeature_32.h | 1 + 7 files changed, 324 insertions(+), 36 deletions(-) create mode 100644 drivers/dma/ioat_dca.c diff --git a/drivers/dca/Kconfig b/drivers/dca/Kconfig index e2f7436da05..94f0364a0ef 100644 --- a/drivers/dca/Kconfig +++ b/drivers/dca/Kconfig @@ -3,9 +3,5 @@ # config DCA - tristate "DCA support for clients and providers" - default m - help - This is a server to help modules that want to use Direct Cache - Access to find DCA providers that will supply correct CPU tags. + tristate diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 8f670dae53b..9c91b0fd134 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -2,42 +2,52 @@ # DMA engine configuration # -menu "DMA Engine support" - depends on HAS_DMA +menuconfig DMADEVICES + bool "DMA Offload Engine support" + depends on (PCI && X86) || ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX + help + Intel(R) offload engines enable offloading memory copies in the + network stack and RAID operations in the MD driver. -config DMA_ENGINE - bool "Support for DMA engines" - ---help--- - DMA engines offload bulk memory operations from the CPU to dedicated - hardware, allowing the operations to happen asynchronously. - -comment "DMA Clients" - -config NET_DMA - bool "Network: TCP receive copy offload" - depends on DMA_ENGINE && NET - default y - ---help--- - This enables the use of DMA engines in the network stack to - offload receive copy-to-user operations, freeing CPU cycles. - Since this is the main user of the DMA engine, it should be enabled; - say Y here. +if DMADEVICES comment "DMA Devices" config INTEL_IOATDMA tristate "Intel I/OAT DMA support" - depends on DMA_ENGINE && PCI - default m - ---help--- - Enable support for the Intel(R) I/OAT DMA engine. + depends on PCI && X86 + select DMA_ENGINE + select DCA + help + Enable support for the Intel(R) I/OAT DMA engine present + in recent Intel Xeon chipsets. + + Say Y here if you have such a chipset. + + If unsure, say N. config INTEL_IOP_ADMA - tristate "Intel IOP ADMA support" - depends on DMA_ENGINE && (ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX) + tristate "Intel IOP ADMA support" + depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX select ASYNC_CORE - default m - ---help--- - Enable support for the Intel(R) IOP Series RAID engines. + select DMA_ENGINE + help + Enable support for the Intel(R) IOP Series RAID engines. -endmenu +config DMA_ENGINE + bool + +comment "DMA Clients" + depends on DMA_ENGINE + +config NET_DMA + bool "Network: TCP receive copy offload" + depends on DMA_ENGINE && NET + default y + help + This enables the use of DMA engines in the network stack to + offload receive copy-to-user operations, freeing CPU cycles. + Since this is the main user of the DMA engine, it should be enabled; + say Y here. + +endif diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index cec0c9c5df6..b152cd84e12 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -1,5 +1,5 @@ obj-$(CONFIG_DMA_ENGINE) += dmaengine.o obj-$(CONFIG_NET_DMA) += iovlock.o obj-$(CONFIG_INTEL_IOATDMA) += ioatdma.o -ioatdma-objs := ioat.o ioat_dma.o +ioatdma-objs := ioat.o ioat_dma.o ioat_dca.o obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o diff --git a/drivers/dma/ioat.c b/drivers/dma/ioat.c index ae5817bfc01..f7276bf2fe7 100644 --- a/drivers/dma/ioat.c +++ b/drivers/dma/ioat.c @@ -1,6 +1,6 @@ /* * Intel I/OAT DMA Linux driver - * Copyright(c) 2004 - 2007 Intel Corporation. + * Copyright(c) 2007 Intel Corporation. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, @@ -29,6 +29,7 @@ #include #include #include +#include #include "ioatdma.h" #include "ioatdma_registers.h" #include "ioatdma_hw.h" @@ -49,6 +50,7 @@ struct ioat_device { struct pci_dev *pdev; void __iomem *iobase; struct ioatdma_device *dma; + struct dca_provider *dca; }; static int __devinit ioat_probe(struct pci_dev *pdev, @@ -57,6 +59,10 @@ static int __devinit ioat_probe(struct pci_dev *pdev, static void __devexit ioat_remove(struct pci_dev *pdev); #endif +static int ioat_dca_enabled = 1; +module_param(ioat_dca_enabled, int, 0644); +MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)"); + static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase) { struct ioat_device *device = pci_get_drvdata(pdev); @@ -67,6 +73,8 @@ static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase) switch (version) { case IOAT_VER_1_2: device->dma = ioat_dma_probe(pdev, iobase); + if (ioat_dca_enabled) + device->dca = ioat_dca_init(pdev, iobase); break; default: err = -ENODEV; @@ -83,6 +91,13 @@ static void ioat_shutdown_functionality(struct pci_dev *pdev) ioat_dma_remove(device->dma); device->dma = NULL; } + + if (device->dca) { + unregister_dca_provider(device->dca); + free_dca_provider(device->dca); + device->dca = NULL; + } + } static struct pci_driver ioat_pci_drv = { diff --git a/drivers/dma/ioat_dca.c b/drivers/dma/ioat_dca.c new file mode 100644 index 00000000000..2ae04c30ede --- /dev/null +++ b/drivers/dma/ioat_dca.c @@ -0,0 +1,263 @@ +/* + * Intel I/OAT DMA Linux driver + * Copyright(c) 2007 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions 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, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + * + */ + +#include +#include +#include +#include +#include + +/* either a kernel change is needed, or we need something like this in kernel */ +#ifndef CONFIG_SMP +#include +#undef cpu_physical_id +#define cpu_physical_id(cpu) (cpuid_ebx(1) >> 24) +#endif + +#include "ioatdma.h" +#include "ioatdma_registers.h" + +/* + * Bit 16 of a tag map entry is the "valid" bit, if it is set then bits 0:15 + * contain the bit number of the APIC ID to map into the DCA tag. If the valid + * bit is not set, then the value must be 0 or 1 and defines the bit in the tag. + */ +#define DCA_TAG_MAP_VALID 0x80 + +/* + * "Legacy" DCA systems do not implement the DCA register set in the + * I/OAT device. Software needs direct support for their tag mappings. + */ + +#define APICID_BIT(x) (DCA_TAG_MAP_VALID | (x)) +#define IOAT_TAG_MAP_LEN 8 + +static u8 ioat_tag_map_BNB[IOAT_TAG_MAP_LEN] = { + 1, APICID_BIT(1), APICID_BIT(2), APICID_BIT(2), }; +static u8 ioat_tag_map_SCNB[IOAT_TAG_MAP_LEN] = { + 1, APICID_BIT(1), APICID_BIT(2), APICID_BIT(2), }; +static u8 ioat_tag_map_CNB[IOAT_TAG_MAP_LEN] = { + 1, APICID_BIT(1), APICID_BIT(3), APICID_BIT(4), APICID_BIT(2), }; +static u8 ioat_tag_map_UNISYS[IOAT_TAG_MAP_LEN] = { 0 }; + +/* pack PCI B/D/F into a u16 */ +static inline u16 dcaid_from_pcidev(struct pci_dev *pci) +{ + return (pci->bus->number << 8) | pci->devfn; +} + +static int dca_enabled_in_bios(void) +{ + /* CPUID level 9 returns DCA configuration */ + /* Bit 0 indicates DCA enabled by the BIOS */ + unsigned long cpuid_level_9; + int res; + + cpuid_level_9 = cpuid_eax(9); + res = test_bit(0, &cpuid_level_9); + if (!res) + printk(KERN_ERR "ioat dma: DCA is disabled in BIOS\n"); + + return res; +} + +static int system_has_dca_enabled(void) +{ + if (boot_cpu_has(X86_FEATURE_DCA)) + return dca_enabled_in_bios(); + + printk(KERN_ERR "ioat dma: boot cpu doesn't have X86_FEATURE_DCA\n"); + return 0; +} + +struct ioat_dca_slot { + struct pci_dev *pdev; /* requester device */ + u16 rid; /* requester id, as used by IOAT */ +}; + +#define IOAT_DCA_MAX_REQ 6 + +struct ioat_dca_priv { + void __iomem *iobase; + void *dca_base; + int max_requesters; + int requester_count; + u8 tag_map[IOAT_TAG_MAP_LEN]; + struct ioat_dca_slot req_slots[0]; +}; + +/* 5000 series chipset DCA Port Requester ID Table Entry Format + * [15:8] PCI-Express Bus Number + * [7:3] PCI-Express Device Number + * [2:0] PCI-Express Function Number + * + * 5000 series chipset DCA control register format + * [7:1] Reserved (0) + * [0] Ignore Function Number + */ + +static int ioat_dca_add_requester(struct dca_provider *dca, struct device *dev) +{ + struct ioat_dca_priv *ioatdca = dca_priv(dca); + struct pci_dev *pdev; + int i; + u16 id; + + /* This implementation only supports PCI-Express */ + if (dev->bus != &pci_bus_type) + return -ENODEV; + pdev = to_pci_dev(dev); + id = dcaid_from_pcidev(pdev); + + if (ioatdca->requester_count == ioatdca->max_requesters) + return -ENODEV; + + for (i = 0; i < ioatdca->max_requesters; i++) { + if (ioatdca->req_slots[i].pdev == NULL) { + /* found an empty slot */ + ioatdca->requester_count++; + ioatdca->req_slots[i].pdev = pdev; + ioatdca->req_slots[i].rid = id; + writew(id, ioatdca->dca_base + (i * 4)); + /* make sure the ignore function bit is off */ + writeb(0, ioatdca->dca_base + (i * 4) + 2); + return i; + } + } + /* Error, ioatdma->requester_count is out of whack */ + return -EFAULT; +} + +static int ioat_dca_remove_requester(struct dca_provider *dca, + struct device *dev) +{ + struct ioat_dca_priv *ioatdca = dca_priv(dca); + struct pci_dev *pdev; + int i; + + /* This implementation only supports PCI-Express */ + if (dev->bus != &pci_bus_type) + return -ENODEV; + pdev = to_pci_dev(dev); + + for (i = 0; i < ioatdca->max_requesters; i++) { + if (ioatdca->req_slots[i].pdev == pdev) { + writew(0, ioatdca->dca_base + (i * 4)); + ioatdca->req_slots[i].pdev = NULL; + ioatdca->req_slots[i].rid = 0; + ioatdca->requester_count--; + return i; + } + } + return -ENODEV; +} + +static u8 ioat_dca_get_tag(struct dca_provider *dca, int cpu) +{ + struct ioat_dca_priv *ioatdca = dca_priv(dca); + int i, apic_id, bit, value; + u8 entry, tag; + + tag = 0; + apic_id = cpu_physical_id(cpu); + + for (i = 0; i < IOAT_TAG_MAP_LEN; i++) { + entry = ioatdca->tag_map[i]; + if (entry & DCA_TAG_MAP_VALID) { + bit = entry & ~DCA_TAG_MAP_VALID; + value = (apic_id & (1 << bit)) ? 1 : 0; + } else { + value = entry ? 1 : 0; + } + tag |= (value << i); + } + return tag; +} + +static struct dca_ops ioat_dca_ops = { + .add_requester = ioat_dca_add_requester, + .remove_requester = ioat_dca_remove_requester, + .get_tag = ioat_dca_get_tag, +}; + + +struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase) +{ + struct dca_provider *dca; + struct ioat_dca_priv *ioatdca; + u8 *tag_map = NULL; + int i; + int err; + + if (!system_has_dca_enabled()) + return NULL; + + /* I/OAT v1 systems must have a known tag_map to support DCA */ + switch (pdev->vendor) { + case PCI_VENDOR_ID_INTEL: + switch (pdev->device) { + case PCI_DEVICE_ID_INTEL_IOAT: + tag_map = ioat_tag_map_BNB; + break; + case PCI_DEVICE_ID_INTEL_IOAT_CNB: + tag_map = ioat_tag_map_CNB; + break; + case PCI_DEVICE_ID_INTEL_IOAT_SCNB: + tag_map = ioat_tag_map_SCNB; + break; + } + break; + case PCI_VENDOR_ID_UNISYS: + switch (pdev->device) { + case PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR: + tag_map = ioat_tag_map_UNISYS; + break; + } + break; + } + if (tag_map == NULL) + return NULL; + + dca = alloc_dca_provider(&ioat_dca_ops, + sizeof(*ioatdca) + + (sizeof(struct ioat_dca_slot) * IOAT_DCA_MAX_REQ)); + if (!dca) + return NULL; + + ioatdca = dca_priv(dca); + ioatdca->max_requesters = IOAT_DCA_MAX_REQ; + + ioatdca->dca_base = iobase + 0x54; + + /* copy over the APIC ID to DCA tag mapping */ + for (i = 0; i < IOAT_TAG_MAP_LEN; i++) + ioatdca->tag_map[i] = tag_map[i]; + + err = register_dca_provider(dca, &pdev->dev); + if (err) { + free_dca_provider(dca); + return NULL; + } + + return dca; +} + diff --git a/drivers/dma/ioatdma.h b/drivers/dma/ioatdma.h index 2abf0b88a97..2a319e124ec 100644 --- a/drivers/dma/ioatdma.h +++ b/drivers/dma/ioatdma.h @@ -132,9 +132,12 @@ struct ioat_desc_sw { struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev, void __iomem *iobase); void ioat_dma_remove(struct ioatdma_device *device); +struct dca_provider *ioat_dca_init(struct pci_dev *pdev, + void __iomem *iobase); #else #define ioat_dma_probe(pdev, iobase) NULL #define ioat_dma_remove(device) do { } while (0) +#define ioat_dca_init(pdev, iobase) NULL #endif #endif /* IOATDMA_H */ diff --git a/include/asm-x86/cpufeature_32.h b/include/asm-x86/cpufeature_32.h index 7b3aa28ebc6..f17e688dfb0 100644 --- a/include/asm-x86/cpufeature_32.h +++ b/include/asm-x86/cpufeature_32.h @@ -92,6 +92,7 @@ #define X86_FEATURE_CID (4*32+10) /* Context ID */ #define X86_FEATURE_CX16 (4*32+13) /* CMPXCHG16B */ #define X86_FEATURE_XTPR (4*32+14) /* Send Task Priority Messages */ +#define X86_FEATURE_DCA (4*32+18) /* Direct Cache Access */ /* VIA/Cyrix/Centaur-defined CPU features, CPUID level 0xC0000001, word 5 */ #define X86_FEATURE_XSTORE (5*32+ 2) /* on-CPU RNG present (xstore insn) */