Commit 27f145e7 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'sparc-pcie-perf' 

Chris Hyser says:

====================
sparc64: PCIe performance enhancements

Ver 2 is redone for 4.8 where commit 00085f1e
changed DMA attributes from struct pointer to unsigned long.

This set of patches initiates a series of PCIe performance enhancement patch
submittals.

Patch 1/2 enables version 2 of the SPARC sun4v IOMMU I/O address translation
services need for subsequent enhancements.

Patch 2/2 allows drivers to specify DMA_ATTR_WEAK_ORDERING via DMA attributes
to the SPARC DMA mapping routines enabling "relaxed ordering" for the buffer
being mapped.

[Still relevant write-up]
PCI-Express Relaxed Ordering and the Sun SPARC Enterprise M-class Servers
https://blogs.oracle.com/olympus/entry/relaxed_ordering


====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents cdd4f4c7 aa7bde1a

arch/sparc/include/asm/hypervisor.h

+1 −0
Original line number Diff line number Diff line
@@ -1744,6 +1744,7 @@ unsigned long sun4v_vintr_set_target(unsigned long dev_handle, 


#define HV_PCI_MAP_ATTR_READ		0x01

#define HV_PCI_MAP_ATTR_WRITE		0x02

#define HV_PCI_MAP_ATTR_RELAXED_ORDER	0x04



#define HV_PCI_DEVICE_BUILD(b,d,f)	\

	((((b) & 0xff) << 16) | \

arch/sparc/kernel/pci_sun4v.c

+41 −11
Original line number Diff line number Diff line
@@ -30,8 +30,19 @@ 
#define DRIVER_NAME	"pci_sun4v"

#define PFX		DRIVER_NAME ": "



static unsigned long vpci_major = 1;

static unsigned long vpci_minor = 1;

static unsigned long vpci_major;

static unsigned long vpci_minor;



struct vpci_version {

	unsigned long major;

	unsigned long minor;

};



/* Ordered from largest major to lowest */

static struct vpci_version vpci_versions[] = {

	{ .major = 2, .minor = 0 },

	{ .major = 1, .minor = 1 },

};



#define PGLIST_NENTS	(PAGE_SIZE / sizeof(u64))
@@ -67,6 +78,10 @@ static long iommu_batch_flush(struct iommu_batch *p) 
	u64 *pglist = p->pglist;

	unsigned long npages = p->npages;



	/* VPCI maj=1, min=[0,1] only supports read and write */

	if (vpci_major < 2)

		prot &= (HV_PCI_MAP_ATTR_READ | HV_PCI_MAP_ATTR_WRITE);



	while (npages != 0) {

		long num;
@@ -133,6 +148,7 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size, 
				   unsigned long attrs)

{

	unsigned long flags, order, first_page, npages, n;

	unsigned long prot = 0;

	struct iommu *iommu;

	struct page *page;

	void *ret;
@@ -146,6 +162,9 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size, 


	npages = size >> IO_PAGE_SHIFT;



	if (attrs & DMA_ATTR_WEAK_ORDERING)

		prot = HV_PCI_MAP_ATTR_RELAXED_ORDER;



	nid = dev->archdata.numa_node;

	page = alloc_pages_node(nid, gfp, order);

	if (unlikely(!page))
@@ -169,7 +188,7 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size, 
	local_irq_save(flags);



	iommu_batch_start(dev,

			  (HV_PCI_MAP_ATTR_READ |

			  (HV_PCI_MAP_ATTR_READ | prot |

			   HV_PCI_MAP_ATTR_WRITE),

			  entry);
@@ -266,6 +285,9 @@ static dma_addr_t dma_4v_map_page(struct device *dev, struct page *page, 
	if (direction != DMA_TO_DEVICE)

		prot |= HV_PCI_MAP_ATTR_WRITE;



	if (attrs & DMA_ATTR_WEAK_ORDERING)

		prot |= HV_PCI_MAP_ATTR_RELAXED_ORDER;



	local_irq_save(flags);



	iommu_batch_start(dev, prot, entry);
@@ -344,6 +366,9 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist, 
	if (direction != DMA_TO_DEVICE)

		prot |= HV_PCI_MAP_ATTR_WRITE;



	if (attrs & DMA_ATTR_WEAK_ORDERING)

		prot |= HV_PCI_MAP_ATTR_RELAXED_ORDER;



	outs = s = segstart = &sglist[0];

	outcount = 1;

	incount = nelems;
@@ -907,21 +932,26 @@ static int pci_sun4v_probe(struct platform_device *op) 
	struct device_node *dp;

	struct iommu *iommu;

	u32 devhandle;

	int i, err;

	int i, err = -ENODEV;



	dp = op->dev.of_node;



	if (!hvapi_negotiated++) {

		err = sun4v_hvapi_register(HV_GRP_PCI,

					   vpci_major,

		for (i = 0; i < ARRAY_SIZE(vpci_versions); i++) {

			vpci_major = vpci_versions[i].major;

			vpci_minor = vpci_versions[i].minor;



			err = sun4v_hvapi_register(HV_GRP_PCI, vpci_major,

						   &vpci_minor);

			if (!err)

				break;

		}



		if (err) {

			printk(KERN_ERR PFX "Could not register hvapi, "

			       "err=%d\n", err);

			pr_err(PFX "Could not register hvapi, err=%d\n", err);

			return err;

		}

		printk(KERN_INFO PFX "Registered hvapi major[%lu] minor[%lu]\n",

		pr_info(PFX "Registered hvapi major[%lu] minor[%lu]\n",

			vpci_major, vpci_minor);



		dma_ops = &sun4v_dma_ops;

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