lan743x: fix endianness when accessing descriptors

TX/RX descriptor ring fields are always little-endian, but conversion
wasn't performed for big-endian CPUs, so the driver failed to work.

This patch makes the driver work on big-endian CPUs. It was tested and
confirmed to work on NXP P1010 processor (PowerPC).

Signed-off-by: Alexey Denisov <rtgbnm@gmail.com>
Link: https://lore.kernel.org/r/20210128044859.280219-1-rtgbnm@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 3804310..51359ce 100644 (file)
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -1253,7 +1253,7 @@ static void lan743x_tx_release_desc(struct lan743x_tx *tx,
        if (!(buffer_info->flags & TX_BUFFER_INFO_FLAG_ACTIVE))
                goto done;
 
-       descriptor_type = (descriptor->data0) &
+       descriptor_type = le32_to_cpu(descriptor->data0) &
                          TX_DESC_DATA0_DTYPE_MASK_;
        if (descriptor_type == TX_DESC_DATA0_DTYPE_DATA_)
                goto clean_up_data_descriptor;
@@ -1313,7 +1313,7 @@ static int lan743x_tx_next_index(struct lan743x_tx *tx, int index)
 
 static void lan743x_tx_release_completed_descriptors(struct lan743x_tx *tx)
 {
-       while ((*tx->head_cpu_ptr) != (tx->last_head)) {
+       while (le32_to_cpu(*tx->head_cpu_ptr) != (tx->last_head)) {
                lan743x_tx_release_desc(tx, tx->last_head, false);
                tx->last_head = lan743x_tx_next_index(tx, tx->last_head);
        }
@@ -1399,10 +1399,10 @@ static int lan743x_tx_frame_start(struct lan743x_tx *tx,
        if (dma_mapping_error(dev, dma_ptr))
                return -ENOMEM;
 
-       tx_descriptor->data1 = DMA_ADDR_LOW32(dma_ptr);
-       tx_descriptor->data2 = DMA_ADDR_HIGH32(dma_ptr);
-       tx_descriptor->data3 = (frame_length << 16) &
-               TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_;
+       tx_descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(dma_ptr));
+       tx_descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(dma_ptr));
+       tx_descriptor->data3 = cpu_to_le32((frame_length << 16) &
+               TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_);
 
        buffer_info->skb = NULL;
        buffer_info->dma_ptr = dma_ptr;
@@ -1443,7 +1443,7 @@ static void lan743x_tx_frame_add_lso(struct lan743x_tx *tx,
                tx->frame_data0 |= TX_DESC_DATA0_IOC_;
        }
        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
-       tx_descriptor->data0 = tx->frame_data0;
+       tx_descriptor->data0 = cpu_to_le32(tx->frame_data0);
 
        /* move to next descriptor */
        tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
@@ -1487,7 +1487,7 @@ static int lan743x_tx_frame_add_fragment(struct lan743x_tx *tx,
 
        /* wrap up previous descriptor */
        tx_descriptor = &tx->ring_cpu_ptr[tx->frame_tail];
-       tx_descriptor->data0 = tx->frame_data0;
+       tx_descriptor->data0 = cpu_to_le32(tx->frame_data0);
 
        /* move to next descriptor */
        tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
@@ -1513,10 +1513,10 @@ static int lan743x_tx_frame_add_fragment(struct lan743x_tx *tx,
                return -ENOMEM;
        }
 
-       tx_descriptor->data1 = DMA_ADDR_LOW32(dma_ptr);
-       tx_descriptor->data2 = DMA_ADDR_HIGH32(dma_ptr);
-       tx_descriptor->data3 = (frame_length << 16) &
-                              TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_;
+       tx_descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(dma_ptr));
+       tx_descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(dma_ptr));
+       tx_descriptor->data3 = cpu_to_le32((frame_length << 16) &
+                              TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_);
 
        buffer_info->skb = NULL;
        buffer_info->dma_ptr = dma_ptr;
@@ -1560,7 +1560,7 @@ static void lan743x_tx_frame_end(struct lan743x_tx *tx,
        if (ignore_sync)
                buffer_info->flags |= TX_BUFFER_INFO_FLAG_IGNORE_SYNC;
 
-       tx_descriptor->data0 = tx->frame_data0;
+       tx_descriptor->data0 = cpu_to_le32(tx->frame_data0);
        tx->frame_tail = lan743x_tx_next_index(tx, tx->frame_tail);
        tx->last_tail = tx->frame_tail;
 
@@ -1967,11 +1967,11 @@ static int lan743x_rx_init_ring_element(struct lan743x_rx *rx, int index,
        }
 
        buffer_info->buffer_length = length;
-       descriptor->data1 = DMA_ADDR_LOW32(buffer_info->dma_ptr);
-       descriptor->data2 = DMA_ADDR_HIGH32(buffer_info->dma_ptr);
+       descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(buffer_info->dma_ptr));
+       descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(buffer_info->dma_ptr));
        descriptor->data3 = 0;
-       descriptor->data0 = (RX_DESC_DATA0_OWN_ |
-                           (length & RX_DESC_DATA0_BUF_LENGTH_MASK_));
+       descriptor->data0 = cpu_to_le32((RX_DESC_DATA0_OWN_ |
+                           (length & RX_DESC_DATA0_BUF_LENGTH_MASK_)));
        skb_reserve(buffer_info->skb, RX_HEAD_PADDING);
        lan743x_rx_update_tail(rx, index);
 
@@ -1986,12 +1986,12 @@ static void lan743x_rx_reuse_ring_element(struct lan743x_rx *rx, int index)
        descriptor = &rx->ring_cpu_ptr[index];
        buffer_info = &rx->buffer_info[index];
 
-       descriptor->data1 = DMA_ADDR_LOW32(buffer_info->dma_ptr);
-       descriptor->data2 = DMA_ADDR_HIGH32(buffer_info->dma_ptr);
+       descriptor->data1 = cpu_to_le32(DMA_ADDR_LOW32(buffer_info->dma_ptr));
+       descriptor->data2 = cpu_to_le32(DMA_ADDR_HIGH32(buffer_info->dma_ptr));
        descriptor->data3 = 0;
-       descriptor->data0 = (RX_DESC_DATA0_OWN_ |
+       descriptor->data0 = cpu_to_le32((RX_DESC_DATA0_OWN_ |
                            ((buffer_info->buffer_length) &
-                           RX_DESC_DATA0_BUF_LENGTH_MASK_));
+                           RX_DESC_DATA0_BUF_LENGTH_MASK_)));
        lan743x_rx_update_tail(rx, index);
 }
 
@@ -2025,7 +2025,7 @@ static int lan743x_rx_process_packet(struct lan743x_rx *rx)
 {
        struct skb_shared_hwtstamps *hwtstamps = NULL;
        int result = RX_PROCESS_RESULT_NOTHING_TO_DO;
-       int current_head_index = *rx->head_cpu_ptr;
+       int current_head_index = le32_to_cpu(*rx->head_cpu_ptr);
        struct lan743x_rx_buffer_info *buffer_info;
        struct lan743x_rx_descriptor *descriptor;
        int extension_index = -1;
@@ -2040,14 +2040,14 @@ static int lan743x_rx_process_packet(struct lan743x_rx *rx)
 
        if (rx->last_head != current_head_index) {
                descriptor = &rx->ring_cpu_ptr[rx->last_head];
-               if (descriptor->data0 & RX_DESC_DATA0_OWN_)
+               if (le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_OWN_)
                        goto done;
 
-               if (!(descriptor->data0 & RX_DESC_DATA0_FS_))
+               if (!(le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_FS_))
                        goto done;
 
                first_index = rx->last_head;
-               if (descriptor->data0 & RX_DESC_DATA0_LS_) {
+               if (le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_LS_) {
                        last_index = rx->last_head;
                } else {
                        int index;
@@ -2055,10 +2055,10 @@ static int lan743x_rx_process_packet(struct lan743x_rx *rx)
                        index = lan743x_rx_next_index(rx, first_index);
                        while (index != current_head_index) {
                                descriptor = &rx->ring_cpu_ptr[index];
-                               if (descriptor->data0 & RX_DESC_DATA0_OWN_)
+                               if (le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_OWN_)
                                        goto done;
 
-                               if (descriptor->data0 & RX_DESC_DATA0_LS_) {
+                               if (le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_LS_) {
                                        last_index = index;
                                        break;
                                }
@@ -2067,17 +2067,17 @@ static int lan743x_rx_process_packet(struct lan743x_rx *rx)
                }
                if (last_index >= 0) {
                        descriptor = &rx->ring_cpu_ptr[last_index];
-                       if (descriptor->data0 & RX_DESC_DATA0_EXT_) {
+                       if (le32_to_cpu(descriptor->data0) & RX_DESC_DATA0_EXT_) {
                                /* extension is expected to follow */
                                int index = lan743x_rx_next_index(rx,
                                                                  last_index);
                                if (index != current_head_index) {
                                        descriptor = &rx->ring_cpu_ptr[index];
-                                       if (descriptor->data0 &
+                                       if (le32_to_cpu(descriptor->data0) &
                                            RX_DESC_DATA0_OWN_) {
                                                goto done;
                                        }
-                                       if (descriptor->data0 &
+                                       if (le32_to_cpu(descriptor->data0) &
                                            RX_DESC_DATA0_EXT_) {
                                                extension_index = index;
                                        } else {
@@ -2129,7 +2129,7 @@ static int lan743x_rx_process_packet(struct lan743x_rx *rx)
                        }
                        buffer_info->skb = NULL;
                        packet_length = RX_DESC_DATA0_FRAME_LENGTH_GET_
-                                       (descriptor->data0);
+                                       (le32_to_cpu(descriptor->data0));
                        skb_put(skb, packet_length - 4);
                        skb->protocol = eth_type_trans(skb,
                                                       rx->adapter->netdev);
@@ -2167,8 +2167,8 @@ process_extension:
                        descriptor = &rx->ring_cpu_ptr[extension_index];
                        buffer_info = &rx->buffer_info[extension_index];
 
-                       ts_sec = descriptor->data1;
-                       ts_nsec = (descriptor->data2 &
+                       ts_sec = le32_to_cpu(descriptor->data1);
+                       ts_nsec = (le32_to_cpu(descriptor->data2) &
                                  RX_DESC_DATA2_TS_NS_MASK_);
                        lan743x_rx_reuse_ring_element(rx, extension_index);
                        real_last_index = extension_index;

diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h
index 404af3f..f3f7789 100644 (file)
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -661,7 +661,7 @@ struct lan743x_tx {
 
        struct lan743x_tx_buffer_info *buffer_info;
 
-       u32             *head_cpu_ptr;
+       __le32          *head_cpu_ptr;
        dma_addr_t      head_dma_ptr;
        int             last_head;
        int             last_tail;
@@ -691,7 +691,7 @@ struct lan743x_rx {
 
        struct lan743x_rx_buffer_info *buffer_info;
 
-       u32             *head_cpu_ptr;
+       __le32          *head_cpu_ptr;
        dma_addr_t      head_dma_ptr;
        u32             last_head;
        u32             last_tail;
@@ -775,10 +775,10 @@ struct lan743x_adapter {
 #define TX_DESC_DATA3_FRAME_LENGTH_MSS_MASK_   (0x3FFF0000)
 
 struct lan743x_tx_descriptor {
-       u32     data0;
-       u32     data1;
-       u32     data2;
-       u32     data3;
+       __le32     data0;
+       __le32     data1;
+       __le32     data2;
+       __le32     data3;
 } __aligned(DEFAULT_DMA_DESCRIPTOR_SPACING);
 
 #define TX_BUFFER_INFO_FLAG_ACTIVE             BIT(0)
@@ -813,10 +813,10 @@ struct lan743x_tx_buffer_info {
 #define RX_HEAD_PADDING                NET_IP_ALIGN
 
 struct lan743x_rx_descriptor {
-       u32     data0;
-       u32     data1;
-       u32     data2;
-       u32     data3;
+       __le32     data0;
+       __le32     data1;
+       __le32     data2;
+       __le32     data3;
 } __aligned(DEFAULT_DMA_DESCRIPTOR_SPACING);
 
 #define RX_BUFFER_INFO_FLAG_ACTIVE      BIT(0)