drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings

[mirror_ubuntu-bionic-kernel.git] / drivers / base / dma-coherent.c

diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index 55b83983a9c00c8b5984c887a0435ffb6e03fe1d..bdf28f7dd5e8638bfee9f522aef1cbfa71b89cbf 100644 (file)
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -2,6 +2,7 @@
  * Coherent per-device memory handling.
  * Borrowed from i386
  */
+#include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -17,9 +18,9 @@ struct dma_coherent_mem {
        spinlock_t      spinlock;
 };
 
-static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_addr,
-                            size_t size, int flags,
-                            struct dma_coherent_mem **mem)
+static bool dma_init_coherent_memory(
+       phys_addr_t phys_addr, dma_addr_t device_addr, size_t size, int flags,
+       struct dma_coherent_mem **mem)
 {
        struct dma_coherent_mem *dma_mem = NULL;
        void __iomem *mem_base = NULL;
@@ -31,7 +32,10 @@ static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_add
        if (!size)
                goto out;
 
-       mem_base = ioremap(phys_addr, size);
+       if (flags & DMA_MEMORY_MAP)
+               mem_base = memremap(phys_addr, size, MEMREMAP_WC);
+       else
+               mem_base = ioremap(phys_addr, size);
        if (!mem_base)
                goto out;
 
@@ -50,24 +54,28 @@ static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_add
        spin_lock_init(&dma_mem->spinlock);
 
        *mem = dma_mem;
-
-       if (flags & DMA_MEMORY_MAP)
-               return DMA_MEMORY_MAP;
-
-       return DMA_MEMORY_IO;
+       return true;
 
 out:
        kfree(dma_mem);
-       if (mem_base)
-               iounmap(mem_base);
-       return 0;
+       if (mem_base) {
+               if (flags & DMA_MEMORY_MAP)
+                       memunmap(mem_base);
+               else
+                       iounmap(mem_base);
+       }
+       return false;
 }
 
 static void dma_release_coherent_memory(struct dma_coherent_mem *mem)
 {
        if (!mem)
                return;
-       iounmap(mem->virt_base);
+
+       if (mem->flags & DMA_MEMORY_MAP)
+               memunmap(mem->virt_base);
+       else
+               iounmap(mem->virt_base);
        kfree(mem->bitmap);
        kfree(mem);
 }
@@ -88,15 +96,13 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
                                dma_addr_t device_addr, size_t size, int flags)
 {
        struct dma_coherent_mem *mem;
-       int ret;
 
-       ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags,
-                                      &mem);
-       if (ret == 0)
+       if (!dma_init_coherent_memory(phys_addr, device_addr, size, flags,
+                                     &mem))
                return 0;
 
        if (dma_assign_coherent_memory(dev, mem) == 0)
-               return ret;
+               return flags & DMA_MEMORY_MAP ? DMA_MEMORY_MAP : DMA_MEMORY_IO;
 
        dma_release_coherent_memory(mem);
        return 0;
@@ -181,7 +187,10 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
         */
        *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
        *ret = mem->virt_base + (pageno << PAGE_SHIFT);
-       memset(*ret, 0, size);
+       if (mem->flags & DMA_MEMORY_MAP)
+               memset(*ret, 0, size);
+       else
+               memset_io(*ret, 0, size);
        spin_unlock_irqrestore(&mem->spinlock, flags);
 
        return 1;
@@ -281,9 +290,9 @@ static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
        struct dma_coherent_mem *mem = rmem->priv;
 
        if (!mem &&
-           dma_init_coherent_memory(rmem->base, rmem->base, rmem->size,
-                                    DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE,
-                                    &mem) != DMA_MEMORY_MAP) {
+           !dma_init_coherent_memory(rmem->base, rmem->base, rmem->size,
+                                     DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE,
+                                     &mem)) {
                pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
                        &rmem->base, (unsigned long)rmem->size / SZ_1M);
                return -ENODEV;