These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

1 files changed, 195 insertions, 35 deletions

diff --git a/kernel/arch/xtensa/kernel/pci-dma.c b/kernel/arch/xtensa/kernel/pci-dma.c
index e8b76b8e4..cd6669834 100644
--- a/kernel/arch/xtensa/kernel/pci-dma.c
+++ b/kernel/arch/xtensa/kernel/pci-dma.c
@@ -1,6 +1,4 @@
 /*
- * arch/xtensa/kernel/pci-dma.c
- *
  * DMA coherent memory allocation.
  *
  * This program is free software; you can redistribute  it and/or modify it
@@ -9,6 +7,7 @@
  * option) any later version.
  *
  * Copyright (C) 2002 - 2005 Tensilica Inc.
+ * Copyright (C) 2015 Cadence Design Systems Inc.
  *
  * Based on version for i386.
  *
@@ -16,22 +15,134 @@
  * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
  */
 
-#include <linux/types.h>
-#include <linux/mm.h>
-#include <linux/string.h>
-#include <linux/pci.h>
 #include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/mm.h>
 #include <linux/module.h>
-#include <asm/io.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+#include <linux/types.h>
 #include <asm/cacheflush.h>
+#include <asm/io.h>
+
+void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+		    enum dma_data_direction dir)
+{
+	switch (dir) {
+	case DMA_BIDIRECTIONAL:
+		__flush_invalidate_dcache_range((unsigned long)vaddr, size);
+		break;
+
+	case DMA_FROM_DEVICE:
+		__invalidate_dcache_range((unsigned long)vaddr, size);
+		break;
+
+	case DMA_TO_DEVICE:
+		__flush_dcache_range((unsigned long)vaddr, size);
+		break;
+
+	case DMA_NONE:
+		BUG();
+		break;
+	}
+}
+EXPORT_SYMBOL(dma_cache_sync);
+
+static void do_cache_op(dma_addr_t dma_handle, size_t size,
+			void (*fn)(unsigned long, unsigned long))
+{
+	unsigned long off = dma_handle & (PAGE_SIZE - 1);
+	unsigned long pfn = PFN_DOWN(dma_handle);
+	struct page *page = pfn_to_page(pfn);
+
+	if (!PageHighMem(page))
+		fn((unsigned long)bus_to_virt(dma_handle), size);
+	else
+		while (size > 0) {
+			size_t sz = min_t(size_t, size, PAGE_SIZE - off);
+			void *vaddr = kmap_atomic(page);
+
+			fn((unsigned long)vaddr + off, sz);
+			kunmap_atomic(vaddr);
+			off = 0;
+			++page;
+			size -= sz;
+		}
+}
+
+static void xtensa_sync_single_for_cpu(struct device *dev,
+				       dma_addr_t dma_handle, size_t size,
+				       enum dma_data_direction dir)
+{
+	switch (dir) {
+	case DMA_BIDIRECTIONAL:
+	case DMA_FROM_DEVICE:
+		do_cache_op(dma_handle, size, __invalidate_dcache_range);
+		break;
+
+	case DMA_NONE:
+		BUG();
+		break;
+
+	default:
+		break;
+	}
+}
+
+static void xtensa_sync_single_for_device(struct device *dev,
+					  dma_addr_t dma_handle, size_t size,
+					  enum dma_data_direction dir)
+{
+	switch (dir) {
+	case DMA_BIDIRECTIONAL:
+	case DMA_TO_DEVICE:
+		if (XCHAL_DCACHE_IS_WRITEBACK)
+			do_cache_op(dma_handle, size, __flush_dcache_range);
+		break;
+
+	case DMA_NONE:
+		BUG();
+		break;
+
+	default:
+		break;
+	}
+}
+
+static void xtensa_sync_sg_for_cpu(struct device *dev,
+				   struct scatterlist *sg, int nents,
+				   enum dma_data_direction dir)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		xtensa_sync_single_for_cpu(dev, sg_dma_address(s),
+					   sg_dma_len(s), dir);
+	}
+}
+
+static void xtensa_sync_sg_for_device(struct device *dev,
+				      struct scatterlist *sg, int nents,
+				      enum dma_data_direction dir)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		xtensa_sync_single_for_device(dev, sg_dma_address(s),
+					      sg_dma_len(s), dir);
+	}
+}
 
 /*
  * Note: We assume that the full memory space is always mapped to 'kseg'
  *	 Otherwise we have to use page attributes (not implemented).
  */
 
-void *
-dma_alloc_coherent(struct device *dev,size_t size,dma_addr_t *handle,gfp_t flag)
+static void *xtensa_dma_alloc(struct device *dev, size_t size,
+			      dma_addr_t *handle, gfp_t flag,
+			      struct dma_attrs *attrs)
 {
 	unsigned long ret;
 	unsigned long uncached = 0;
@@ -52,20 +163,15 @@ dma_alloc_coherent(struct device *dev,size_t size,dma_addr_t *handle,gfp_t flag)
 	BUG_ON(ret < XCHAL_KSEG_CACHED_VADDR ||
 	       ret > XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_SIZE - 1);
 
+	uncached = ret + XCHAL_KSEG_BYPASS_VADDR - XCHAL_KSEG_CACHED_VADDR;
+	*handle = virt_to_bus((void *)ret);
+	__invalidate_dcache_range(ret, size);
 
-	if (ret != 0) {
-		memset((void*) ret, 0, size);
-		uncached = ret+XCHAL_KSEG_BYPASS_VADDR-XCHAL_KSEG_CACHED_VADDR;
-		*handle = virt_to_bus((void*)ret);
-		__flush_invalidate_dcache_range(ret, size);
-	}
-
-	return (void*)uncached;
+	return (void *)uncached;
 }
-EXPORT_SYMBOL(dma_alloc_coherent);
 
-void dma_free_coherent(struct device *hwdev, size_t size,
-			 void *vaddr, dma_addr_t dma_handle)
+static void xtensa_dma_free(struct device *hwdev, size_t size, void *vaddr,
+			    dma_addr_t dma_handle, struct dma_attrs *attrs)
 {
 	unsigned long addr = (unsigned long)vaddr +
 		XCHAL_KSEG_CACHED_VADDR - XCHAL_KSEG_BYPASS_VADDR;
@@ -75,24 +181,78 @@ void dma_free_coherent(struct device *hwdev, size_t size,
 
 	free_pages(addr, get_order(size));
 }
-EXPORT_SYMBOL(dma_free_coherent);
 
+static dma_addr_t xtensa_map_page(struct device *dev, struct page *page,
+				  unsigned long offset, size_t size,
+				  enum dma_data_direction dir,
+				  struct dma_attrs *attrs)
+{
+	dma_addr_t dma_handle = page_to_phys(page) + offset;
 
-void consistent_sync(void *vaddr, size_t size, int direction)
+	xtensa_sync_single_for_device(dev, dma_handle, size, dir);
+	return dma_handle;
+}
+
+static void xtensa_unmap_page(struct device *dev, dma_addr_t dma_handle,
+			      size_t size, enum dma_data_direction dir,
+			      struct dma_attrs *attrs)
 {
-	switch (direction) {
-	case PCI_DMA_NONE:
-		BUG();
-	case PCI_DMA_FROMDEVICE:        /* invalidate only */
-		__invalidate_dcache_range((unsigned long)vaddr,
-				          (unsigned long)size);
-		break;
+	xtensa_sync_single_for_cpu(dev, dma_handle, size, dir);
+}
 
-	case PCI_DMA_TODEVICE:          /* writeback only */
-	case PCI_DMA_BIDIRECTIONAL:     /* writeback and invalidate */
-		__flush_invalidate_dcache_range((unsigned long)vaddr,
-				    		(unsigned long)size);
-		break;
+static int xtensa_map_sg(struct device *dev, struct scatterlist *sg,
+			 int nents, enum dma_data_direction dir,
+			 struct dma_attrs *attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		s->dma_address = xtensa_map_page(dev, sg_page(s), s->offset,
+						 s->length, dir, attrs);
+	}
+	return nents;
+}
+
+static void xtensa_unmap_sg(struct device *dev,
+			    struct scatterlist *sg, int nents,
+			    enum dma_data_direction dir,
+			    struct dma_attrs *attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		xtensa_unmap_page(dev, sg_dma_address(s),
+				  sg_dma_len(s), dir, attrs);
 	}
 }
-EXPORT_SYMBOL(consistent_sync);
+
+int xtensa_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return 0;
+}
+
+struct dma_map_ops xtensa_dma_map_ops = {
+	.alloc = xtensa_dma_alloc,
+	.free = xtensa_dma_free,
+	.map_page = xtensa_map_page,
+	.unmap_page = xtensa_unmap_page,
+	.map_sg = xtensa_map_sg,
+	.unmap_sg = xtensa_unmap_sg,
+	.sync_single_for_cpu = xtensa_sync_single_for_cpu,
+	.sync_single_for_device = xtensa_sync_single_for_device,
+	.sync_sg_for_cpu = xtensa_sync_sg_for_cpu,
+	.sync_sg_for_device = xtensa_sync_sg_for_device,
+	.mapping_error = xtensa_dma_mapping_error,
+};
+EXPORT_SYMBOL(xtensa_dma_map_ops);
+
+#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
+
+static int __init xtensa_dma_init(void)
+{
+	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
+	return 0;
+}
+fs_initcall(xtensa_dma_init);