[PATCH 5.10 71/77] lan743x: fix endianness when accessing descriptors

From: Greg Kroah-Hartman
Date: Mon Nov 01 2021 - 05:39:20 EST


From: Alexey Denisov <rtgbnm@xxxxxxxxx>

[ Upstream commit 462512824f902a24de794290dd622e664587da1d ]

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@xxxxxxxxx>
Link: https://lore.kernel.org/r/20210128044859.280219-1-rtgbnm@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/microchip/lan743x_main.c | 66 +++++++++----------
drivers/net/ethernet/microchip/lan743x_main.h | 20 +++---
2 files changed, 43 insertions(+), 43 deletions(-)

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 3355e0a5b272..e14dfaafe439 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -1280,7 +1280,7 @@ 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;
@@ -1340,7 +1340,7 @@ 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);
}
@@ -1426,10 +1426,10 @@ 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;
@@ -1470,7 +1470,7 @@ 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);
@@ -1514,7 +1514,7 @@ 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);
@@ -1540,10 +1540,10 @@ 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;
@@ -1587,7 +1587,7 @@ 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;

@@ -2004,11 +2004,11 @@ 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);

@@ -2023,12 +2023,12 @@ 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);
}

@@ -2062,7 +2062,7 @@ 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;
@@ -2077,14 +2077,14 @@ 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;
@@ -2092,10 +2092,10 @@ 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;
}
@@ -2104,17 +2104,17 @@ 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 {
@@ -2166,7 +2166,7 @@ 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);
@@ -2204,8 +2204,8 @@ 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 a536f4a4994d..751f2bc9ce84 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -660,7 +660,7 @@ 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;
@@ -690,7 +690,7 @@ 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)
--
2.33.0