mmc: dw_mmc: split out preparation of desc for IDMAC32 and IDMAC64

We intend to add more check for descriptors when
preparing desc. Let's spilt out the separate body
to make the dw_mci_translate_sglist not so lengthy.
After spliting out these two functions, we could
remove dw_mci_translate_sglist and call both of them
when staring idmac.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 79 insertions, 70 deletions

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index c23e252c037f..ff9b0fcf8300 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -467,112 +467,121 @@ static void dw_mci_dmac_complete_dma(void *arg)
         }
 }
 
-static void dw_mci_translate_sglist(struct dw_mci *host, struct mmc_data *data,
-                                    unsigned int sg_len)
+static inline void dw_mci_prepare_desc64(struct dw_mci *host,
+                                         struct mmc_data *data,
+                                         unsigned int sg_len)
 {
         unsigned int desc_len;
+        struct idmac_desc_64addr *desc_first, *desc_last, *desc;
         int i;
 
-        if (host->dma_64bit_address == 1) {
-                struct idmac_desc_64addr *desc_first, *desc_last, *desc;
-
-                desc_first = desc_last = desc = host->sg_cpu;
+        desc_first = desc_last = desc = host->sg_cpu;
 
-                for (i = 0; i < sg_len; i++) {
-                        unsigned int length = sg_dma_len(&data->sg[i]);
+        for (i = 0; i < sg_len; i++) {
+                unsigned int length = sg_dma_len(&data->sg[i]);
 
-                        u64 mem_addr = sg_dma_address(&data->sg[i]);
+                u64 mem_addr = sg_dma_address(&data->sg[i]);
 
-                        for ( ; length ; desc++) {
-                                desc_len = (length <= DW_MCI_DESC_DATA_LENGTH) ?
-                                           length : DW_MCI_DESC_DATA_LENGTH;
+                for ( ; length ; desc++) {
+                        desc_len = (length <= DW_MCI_DESC_DATA_LENGTH) ?
+                                   length : DW_MCI_DESC_DATA_LENGTH;
 
-                                length -= desc_len;
+                        length -= desc_len;
 
-                                /*
-                                 * Set the OWN bit and disable interrupts
-                                 * for this descriptor
-                                 */
-                                desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC |
-                                                        IDMAC_DES0_CH;
+                        /*
+                         * Set the OWN bit and disable interrupts
+                         * for this descriptor
+                         */
+                        desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC |
+                                                IDMAC_DES0_CH;
 
-                                /* Buffer length */
-                                IDMAC_64ADDR_SET_BUFFER1_SIZE(desc, desc_len);
+                        /* Buffer length */
+                        IDMAC_64ADDR_SET_BUFFER1_SIZE(desc, desc_len);
 
-                                /* Physical address to DMA to/from */
-                                desc->des4 = mem_addr & 0xffffffff;
-                                desc->des5 = mem_addr >> 32;
+                        /* Physical address to DMA to/from */
+                        desc->des4 = mem_addr & 0xffffffff;
+                        desc->des5 = mem_addr >> 32;
 
-                                /* Update physical address for the next desc */
-                                mem_addr += desc_len;
+                        /* Update physical address for the next desc */
+                        mem_addr += desc_len;
 
-                                /* Save pointer to the last descriptor */
-                                desc_last = desc;
-                        }
+                        /* Save pointer to the last descriptor */
+                        desc_last = desc;
                 }
+        }
 
-                /* Set first descriptor */
-                desc_first->des0 |= IDMAC_DES0_FD;
+        /* Set first descriptor */
+        desc_first->des0 |= IDMAC_DES0_FD;
 
-                /* Set last descriptor */
-                desc_last->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
-                desc_last->des0 |= IDMAC_DES0_LD;
+        /* Set last descriptor */
+        desc_last->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
+        desc_last->des0 |= IDMAC_DES0_LD;
+}
 
-        } else {
-                struct idmac_desc *desc_first, *desc_last, *desc;
 
-                desc_first = desc_last = desc = host->sg_cpu;
+static inline void dw_mci_prepare_desc32(struct dw_mci *host,
+                                         struct mmc_data *data,
+                                         unsigned int sg_len)
+{
+        unsigned int desc_len;
+        struct idmac_desc *desc_first, *desc_last, *desc;
+        int i;
 
-                for (i = 0; i < sg_len; i++) {
-                        unsigned int length = sg_dma_len(&data->sg[i]);
+        desc_first = desc_last = desc = host->sg_cpu;
 
-                        u32 mem_addr = sg_dma_address(&data->sg[i]);
+        for (i = 0; i < sg_len; i++) {
+                unsigned int length = sg_dma_len(&data->sg[i]);
 
-                        for ( ; length ; desc++) {
-                                desc_len = (length <= DW_MCI_DESC_DATA_LENGTH) ?
-                                           length : DW_MCI_DESC_DATA_LENGTH;
+                u32 mem_addr = sg_dma_address(&data->sg[i]);
 
-                                length -= desc_len;
+                for ( ; length ; desc++) {
+                        desc_len = (length <= DW_MCI_DESC_DATA_LENGTH) ?
+                                   length : DW_MCI_DESC_DATA_LENGTH;
 
-                                /*
-                                 * Set the OWN bit and disable interrupts
-                                 * for this descriptor
-                                 */
-                                desc->des0 = cpu_to_le32(IDMAC_DES0_OWN |
-                                                         IDMAC_DES0_DIC |
-                                                         IDMAC_DES0_CH);
+                        length -= desc_len;
 
-                                /* Buffer length */
-                                IDMAC_SET_BUFFER1_SIZE(desc, desc_len);
+                        /*
+                         * Set the OWN bit and disable interrupts
+                         * for this descriptor
+                         */
+                        desc->des0 = cpu_to_le32(IDMAC_DES0_OWN |
+                                                 IDMAC_DES0_DIC |
+                                                 IDMAC_DES0_CH);
 
-                                /* Physical address to DMA to/from */
-                                desc->des2 = cpu_to_le32(mem_addr);
+                        /* Buffer length */
+                        IDMAC_SET_BUFFER1_SIZE(desc, desc_len);
 
-                                /* Update physical address for the next desc */
-                                mem_addr += desc_len;
+                        /* Physical address to DMA to/from */
+                        desc->des2 = cpu_to_le32(mem_addr);
 
-                                /* Save pointer to the last descriptor */
-                                desc_last = desc;
-                        }
-                }
-
-                /* Set first descriptor */
-                desc_first->des0 |= cpu_to_le32(IDMAC_DES0_FD);
+                        /* Update physical address for the next desc */
+                        mem_addr += desc_len;
 
-                /* Set last descriptor */
-                desc_last->des0 &= cpu_to_le32(~(IDMAC_DES0_CH |
-                                               IDMAC_DES0_DIC));
-                desc_last->des0 |= cpu_to_le32(IDMAC_DES0_LD);
+                        /* Save pointer to the last descriptor */
+                        desc_last = desc;
+                }
         }
 
-        wmb(); /* drain writebuffer */
+        /* Set first descriptor */
+        desc_first->des0 |= cpu_to_le32(IDMAC_DES0_FD);
+
+        /* Set last descriptor */
+        desc_last->des0 &= cpu_to_le32(~(IDMAC_DES0_CH |
+                                       IDMAC_DES0_DIC));
+        desc_last->des0 |= cpu_to_le32(IDMAC_DES0_LD);
 }
 
 static int dw_mci_idmac_start_dma(struct dw_mci *host, unsigned int sg_len)
 {
         u32 temp;
 
-        dw_mci_translate_sglist(host, host->data, sg_len);
+        if (host->dma_64bit_address == 1)
+                dw_mci_prepare_desc64(host, host->data, sg_len);
+        else
+                dw_mci_prepare_desc32(host, host->data, sg_len);
+
+        /* drain writebuffer */
+        wmb();
 
         /* Make sure to reset DMA in case we did PIO before this */
         dw_mci_ctrl_reset(host, SDMMC_CTRL_DMA_RESET);