+static char *sdhci_kmap_atomic(struct scatterlist *sg, unsigned long *flags)
+{
+ local_irq_save(*flags);
+ return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
+}
+
+static void sdhci_kunmap_atomic(void *buffer, unsigned long *flags)
+{
+ kunmap_atomic(buffer, KM_BIO_SRC_IRQ);
+ local_irq_restore(*flags);
+}
+
+static int sdhci_adma_table_pre(struct sdhci_host *host,
+ struct mmc_data *data)
+{
+ int direction;
+
+ u8 *desc;
+ u8 *align;
+ dma_addr_t addr;
+ dma_addr_t align_addr;
+ int len, offset;
+
+ struct scatterlist *sg;
+ int i;
+ char *buffer;
+ unsigned long flags;
+
+ /*
+ * The spec does not specify endianness of descriptor table.
+ * We currently guess that it is LE.
+ */
+
+ if (data->flags & MMC_DATA_READ)
+ direction = DMA_FROM_DEVICE;
+ else
+ direction = DMA_TO_DEVICE;
+
+ /*
+ * The ADMA descriptor table is mapped further down as we
+ * need to fill it with data first.
+ */
+
+ host->align_addr = dma_map_single(mmc_dev(host->mmc),
+ host->align_buffer, 128 * 4, direction);
+ if (dma_mapping_error(mmc_dev(host->mmc), host->align_addr))
+ goto fail;
+ BUG_ON(host->align_addr & 0x3);
+
+ host->sg_count = dma_map_sg(mmc_dev(host->mmc),
+ data->sg, data->sg_len, direction);
+ if (host->sg_count == 0)
+ goto unmap_align;
+
+ desc = host->adma_desc;
+ align = host->align_buffer;
+
+ align_addr = host->align_addr;
+
+ for_each_sg(data->sg, sg, host->sg_count, i) {
+ addr = sg_dma_address(sg);
+ len = sg_dma_len(sg);
+
+ /*
+ * The SDHCI specification states that ADMA
+ * addresses must be 32-bit aligned. If they
+ * aren't, then we use a bounce buffer for
+ * the (up to three) bytes that screw up the
+ * alignment.
+ */
+ offset = (4 - (addr & 0x3)) & 0x3;
+ if (offset) {
+ if (data->flags & MMC_DATA_WRITE) {
+ buffer = sdhci_kmap_atomic(sg, &flags);
+ WARN_ON(((long)buffer & PAGE_MASK) > (PAGE_SIZE - 3));
+ memcpy(align, buffer, offset);
+ sdhci_kunmap_atomic(buffer, &flags);
+ }
+
+ desc[7] = (align_addr >> 24) & 0xff;
+ desc[6] = (align_addr >> 16) & 0xff;
+ desc[5] = (align_addr >> 8) & 0xff;
+ desc[4] = (align_addr >> 0) & 0xff;
+
+ BUG_ON(offset > 65536);
+
+ desc[3] = (offset >> 8) & 0xff;
+ desc[2] = (offset >> 0) & 0xff;
+
+ desc[1] = 0x00;
+ desc[0] = 0x21; /* tran, valid */
+
+ align += 4;
+ align_addr += 4;
+
+ desc += 8;
+
+ addr += offset;
+ len -= offset;
+ }
+
+ desc[7] = (addr >> 24) & 0xff;
+ desc[6] = (addr >> 16) & 0xff;
+ desc[5] = (addr >> 8) & 0xff;
+ desc[4] = (addr >> 0) & 0xff;
+
+ BUG_ON(len > 65536);
+
+ desc[3] = (len >> 8) & 0xff;
+ desc[2] = (len >> 0) & 0xff;
+
+ desc[1] = 0x00;
+ desc[0] = 0x21; /* tran, valid */
+
+ desc += 8;
+
+ /*
+ * If this triggers then we have a calculation bug
+ * somewhere. :/
+ */
+ WARN_ON((desc - host->adma_desc) > (128 * 2 + 1) * 4);
+ }
+
+ /*
+ * Add a terminating entry.
+ */
+ desc[7] = 0;
+ desc[6] = 0;
+ desc[5] = 0;
+ desc[4] = 0;
+
+ desc[3] = 0;
+ desc[2] = 0;
+
+ desc[1] = 0x00;
+ desc[0] = 0x03; /* nop, end, valid */
+
+ /*
+ * Resync align buffer as we might have changed it.
+ */
+ if (data->flags & MMC_DATA_WRITE) {
+ dma_sync_single_for_device(mmc_dev(host->mmc),
+ host->align_addr, 128 * 4, direction);
+ }
+
+ host->adma_addr = dma_map_single(mmc_dev(host->mmc),
+ host->adma_desc, (128 * 2 + 1) * 4, DMA_TO_DEVICE);
+ if (dma_mapping_error(mmc_dev(host->mmc), host->adma_addr))
+ goto unmap_entries;
+ BUG_ON(host->adma_addr & 0x3);
+
+ return 0;
+
+unmap_entries:
+ dma_unmap_sg(mmc_dev(host->mmc), data->sg,
+ data->sg_len, direction);
+unmap_align:
+ dma_unmap_single(mmc_dev(host->mmc), host->align_addr,
+ 128 * 4, direction);
+fail:
+ return -EINVAL;
+}
+
+static void sdhci_adma_table_post(struct sdhci_host *host,
+ struct mmc_data *data)
+{
+ int direction;
+
+ struct scatterlist *sg;
+ int i, size;
+ u8 *align;
+ char *buffer;
+ unsigned long flags;
+
+ if (data->flags & MMC_DATA_READ)
+ direction = DMA_FROM_DEVICE;
+ else
+ direction = DMA_TO_DEVICE;
+
+ dma_unmap_single(mmc_dev(host->mmc), host->adma_addr,
+ (128 * 2 + 1) * 4, DMA_TO_DEVICE);
+
+ dma_unmap_single(mmc_dev(host->mmc), host->align_addr,
+ 128 * 4, direction);
+
+ if (data->flags & MMC_DATA_READ) {
+ dma_sync_sg_for_cpu(mmc_dev(host->mmc), data->sg,
+ data->sg_len, direction);
+
+ align = host->align_buffer;
+
+ for_each_sg(data->sg, sg, host->sg_count, i) {
+ if (sg_dma_address(sg) & 0x3) {
+ size = 4 - (sg_dma_address(sg) & 0x3);
+
+ buffer = sdhci_kmap_atomic(sg, &flags);
+ WARN_ON(((long)buffer & PAGE_MASK) > (PAGE_SIZE - 3));
+ memcpy(buffer, align, size);
+ sdhci_kunmap_atomic(buffer, &flags);
+
+ align += 4;
+ }
+ }
+ }
+
+ dma_unmap_sg(mmc_dev(host->mmc), data->sg,
+ data->sg_len, direction);
+}
+