Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / dma / coh901318_lli.c
diff --git a/kernel/drivers/dma/coh901318_lli.c b/kernel/drivers/dma/coh901318_lli.c
new file mode 100644 (file)
index 0000000..702112d
--- /dev/null
@@ -0,0 +1,313 @@
+/*
+ * driver/dma/coh901318_lli.c
+ *
+ * Copyright (C) 2007-2009 ST-Ericsson
+ * License terms: GNU General Public License (GPL) version 2
+ * Support functions for handling lli for dma
+ * Author: Per Friden <per.friden@stericsson.com>
+ */
+
+#include <linux/spinlock.h>
+#include <linux/memory.h>
+#include <linux/gfp.h>
+#include <linux/dmapool.h>
+#include <linux/dmaengine.h>
+
+#include "coh901318.h"
+
+#if (defined(CONFIG_DEBUG_FS) && defined(CONFIG_U300_DEBUG))
+#define DEBUGFS_POOL_COUNTER_RESET(pool) (pool->debugfs_pool_counter = 0)
+#define DEBUGFS_POOL_COUNTER_ADD(pool, add) (pool->debugfs_pool_counter += add)
+#else
+#define DEBUGFS_POOL_COUNTER_RESET(pool)
+#define DEBUGFS_POOL_COUNTER_ADD(pool, add)
+#endif
+
+static struct coh901318_lli *
+coh901318_lli_next(struct coh901318_lli *data)
+{
+       if (data == NULL || data->link_addr == 0)
+               return NULL;
+
+       return (struct coh901318_lli *) data->virt_link_addr;
+}
+
+int coh901318_pool_create(struct coh901318_pool *pool,
+                         struct device *dev,
+                         size_t size, size_t align)
+{
+       spin_lock_init(&pool->lock);
+       pool->dev = dev;
+       pool->dmapool = dma_pool_create("lli_pool", dev, size, align, 0);
+
+       DEBUGFS_POOL_COUNTER_RESET(pool);
+       return 0;
+}
+
+int coh901318_pool_destroy(struct coh901318_pool *pool)
+{
+
+       dma_pool_destroy(pool->dmapool);
+       return 0;
+}
+
+struct coh901318_lli *
+coh901318_lli_alloc(struct coh901318_pool *pool, unsigned int len)
+{
+       int i;
+       struct coh901318_lli *head;
+       struct coh901318_lli *lli;
+       struct coh901318_lli *lli_prev;
+       dma_addr_t phy;
+
+       if (len == 0)
+               return NULL;
+
+       spin_lock(&pool->lock);
+
+       head = dma_pool_alloc(pool->dmapool, GFP_NOWAIT, &phy);
+
+       if (head == NULL)
+               goto err;
+
+       DEBUGFS_POOL_COUNTER_ADD(pool, 1);
+
+       lli = head;
+       lli->phy_this = phy;
+       lli->link_addr = 0x00000000;
+       lli->virt_link_addr = 0x00000000U;
+
+       for (i = 1; i < len; i++) {
+               lli_prev = lli;
+
+               lli = dma_pool_alloc(pool->dmapool, GFP_NOWAIT, &phy);
+
+               if (lli == NULL)
+                       goto err_clean_up;
+
+               DEBUGFS_POOL_COUNTER_ADD(pool, 1);
+               lli->phy_this = phy;
+               lli->link_addr = 0x00000000;
+               lli->virt_link_addr = 0x00000000U;
+
+               lli_prev->link_addr = phy;
+               lli_prev->virt_link_addr = lli;
+       }
+
+       spin_unlock(&pool->lock);
+
+       return head;
+
+ err:
+       spin_unlock(&pool->lock);
+       return NULL;
+
+ err_clean_up:
+       lli_prev->link_addr = 0x00000000U;
+       spin_unlock(&pool->lock);
+       coh901318_lli_free(pool, &head);
+       return NULL;
+}
+
+void coh901318_lli_free(struct coh901318_pool *pool,
+                       struct coh901318_lli **lli)
+{
+       struct coh901318_lli *l;
+       struct coh901318_lli *next;
+
+       if (lli == NULL)
+               return;
+
+       l = *lli;
+
+       if (l == NULL)
+               return;
+
+       spin_lock(&pool->lock);
+
+       while (l->link_addr) {
+               next = l->virt_link_addr;
+               dma_pool_free(pool->dmapool, l, l->phy_this);
+               DEBUGFS_POOL_COUNTER_ADD(pool, -1);
+               l = next;
+       }
+       dma_pool_free(pool->dmapool, l, l->phy_this);
+       DEBUGFS_POOL_COUNTER_ADD(pool, -1);
+
+       spin_unlock(&pool->lock);
+       *lli = NULL;
+}
+
+int
+coh901318_lli_fill_memcpy(struct coh901318_pool *pool,
+                         struct coh901318_lli *lli,
+                         dma_addr_t source, unsigned int size,
+                         dma_addr_t destination, u32 ctrl_chained,
+                         u32 ctrl_eom)
+{
+       int s = size;
+       dma_addr_t src = source;
+       dma_addr_t dst = destination;
+
+       lli->src_addr = src;
+       lli->dst_addr = dst;
+
+       while (lli->link_addr) {
+               lli->control = ctrl_chained | MAX_DMA_PACKET_SIZE;
+               lli->src_addr = src;
+               lli->dst_addr = dst;
+
+               s -= MAX_DMA_PACKET_SIZE;
+               lli = coh901318_lli_next(lli);
+
+               src += MAX_DMA_PACKET_SIZE;
+               dst += MAX_DMA_PACKET_SIZE;
+       }
+
+       lli->control = ctrl_eom | s;
+       lli->src_addr = src;
+       lli->dst_addr = dst;
+
+       return 0;
+}
+
+int
+coh901318_lli_fill_single(struct coh901318_pool *pool,
+                         struct coh901318_lli *lli,
+                         dma_addr_t buf, unsigned int size,
+                         dma_addr_t dev_addr, u32 ctrl_chained, u32 ctrl_eom,
+                         enum dma_transfer_direction dir)
+{
+       int s = size;
+       dma_addr_t src;
+       dma_addr_t dst;
+
+
+       if (dir == DMA_MEM_TO_DEV) {
+               src = buf;
+               dst = dev_addr;
+
+       } else if (dir == DMA_DEV_TO_MEM) {
+
+               src = dev_addr;
+               dst = buf;
+       } else {
+               return -EINVAL;
+       }
+
+       while (lli->link_addr) {
+               size_t block_size = MAX_DMA_PACKET_SIZE;
+               lli->control = ctrl_chained | MAX_DMA_PACKET_SIZE;
+
+               /* If we are on the next-to-final block and there will
+                * be less than half a DMA packet left for the last
+                * block, then we want to make this block a little
+                * smaller to balance the sizes. This is meant to
+                * avoid too small transfers if the buffer size is
+                * (MAX_DMA_PACKET_SIZE*N + 1) */
+               if (s < (MAX_DMA_PACKET_SIZE + MAX_DMA_PACKET_SIZE/2))
+                       block_size = MAX_DMA_PACKET_SIZE/2;
+
+               s -= block_size;
+               lli->src_addr = src;
+               lli->dst_addr = dst;
+
+               lli = coh901318_lli_next(lli);
+
+               if (dir == DMA_MEM_TO_DEV)
+                       src += block_size;
+               else if (dir == DMA_DEV_TO_MEM)
+                       dst += block_size;
+       }
+
+       lli->control = ctrl_eom | s;
+       lli->src_addr = src;
+       lli->dst_addr = dst;
+
+       return 0;
+}
+
+int
+coh901318_lli_fill_sg(struct coh901318_pool *pool,
+                     struct coh901318_lli *lli,
+                     struct scatterlist *sgl, unsigned int nents,
+                     dma_addr_t dev_addr, u32 ctrl_chained, u32 ctrl,
+                     u32 ctrl_last,
+                     enum dma_transfer_direction dir, u32 ctrl_irq_mask)
+{
+       int i;
+       struct scatterlist *sg;
+       u32 ctrl_sg;
+       dma_addr_t src = 0;
+       dma_addr_t dst = 0;
+       u32 bytes_to_transfer;
+       u32 elem_size;
+
+       if (lli == NULL)
+               goto err;
+
+       spin_lock(&pool->lock);
+
+       if (dir == DMA_MEM_TO_DEV)
+               dst = dev_addr;
+       else if (dir == DMA_DEV_TO_MEM)
+               src = dev_addr;
+       else
+               goto err;
+
+       for_each_sg(sgl, sg, nents, i) {
+               if (sg_is_chain(sg)) {
+                       /* sg continues to the next sg-element don't
+                        * send ctrl_finish until the last
+                        * sg-element in the chain
+                        */
+                       ctrl_sg = ctrl_chained;
+               } else if (i == nents - 1)
+                       ctrl_sg = ctrl_last;
+               else
+                       ctrl_sg = ctrl ? ctrl : ctrl_last;
+
+
+               if (dir == DMA_MEM_TO_DEV)
+                       /* increment source address */
+                       src = sg_dma_address(sg);
+               else
+                       /* increment destination address */
+                       dst = sg_dma_address(sg);
+
+               bytes_to_transfer = sg_dma_len(sg);
+
+               while (bytes_to_transfer) {
+                       u32 val;
+
+                       if (bytes_to_transfer > MAX_DMA_PACKET_SIZE) {
+                               elem_size = MAX_DMA_PACKET_SIZE;
+                               val = ctrl_chained;
+                       } else {
+                               elem_size = bytes_to_transfer;
+                               val = ctrl_sg;
+                       }
+
+                       lli->control = val | elem_size;
+                       lli->src_addr = src;
+                       lli->dst_addr = dst;
+
+                       if (dir == DMA_DEV_TO_MEM)
+                               dst += elem_size;
+                       else
+                               src += elem_size;
+
+                       BUG_ON(lli->link_addr & 3);
+
+                       bytes_to_transfer -= elem_size;
+                       lli = coh901318_lli_next(lli);
+               }
+
+       }
+       spin_unlock(&pool->lock);
+
+       return 0;
+ err:
+       spin_unlock(&pool->lock);
+       return -EINVAL;
+}