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 <[email protected]>
Acked-by: David S. Miller <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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
 

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.
+
+if DMADEVICES
+
+comment "DMA Devices"
+
+config INTEL_IOATDMA
+	tristate "Intel I/OAT DMA support"
+	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 ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX
+	select ASYNC_CORE
+	select DMA_ENGINE
+	help
+	  Enable support for the Intel(R) IOP Series RAID engines.
 
 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.
+	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---
+	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.
 
-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.
-
-config INTEL_IOP_ADMA
-        tristate "Intel IOP ADMA support"
-        depends on DMA_ENGINE && (ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX)
-	select ASYNC_CORE
-        default m
-        ---help---
-          Enable support for the Intel(R) IOP Series RAID engines.
-
-endmenu
+endif

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

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 <linux/module.h>
 #include <linux/pci.h>
 #include <linux/interrupt.h>
+#include <linux/dca.h>
 #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 = {