diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h index f9e87fb33da0..7ec40c4b2d5a 100644 --- a/drivers/net/dsa/sja1105/sja1105.h +++ b/drivers/net/dsa/sja1105/sja1105.h @@ -209,6 +209,7 @@ struct sja1105_private { unsigned long ucast_egress_floods; unsigned long bcast_egress_floods; const struct sja1105_info *info; + size_t max_xfer_len; struct gpio_desc *reset_gpio; struct spi_device *spidev; struct dsa_switch *ds; diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index 405024b637d6..802314e90e64 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -3563,6 +3563,7 @@ static int sja1105_probe(struct spi_device *spi) struct sja1105_tagger_data *tagger_data; struct device *dev = &spi->dev; struct sja1105_private *priv; + size_t max_xfer, max_msg; struct dsa_switch *ds; int rc, port; @@ -3596,6 +3597,33 @@ static int sja1105_probe(struct spi_device *spi) return rc; } + /* In sja1105_xfer, we send spi_messages composed of two spi_transfers: + * a small one for the message header and another one for the current + * chunk of the packed buffer. + * Check that the restrictions imposed by the SPI controller are + * respected: the chunk buffer is smaller than the max transfer size, + * and the total length of the chunk plus its message header is smaller + * than the max message size. + * We do that during probe time since the maximum transfer size is a + * runtime invariant. + */ + max_xfer = spi_max_transfer_size(spi); + max_msg = spi_max_message_size(spi); + + /* We need to send at least one 64-bit word of SPI payload per message + * in order to be able to make useful progress. + */ + if (max_msg < SJA1105_SIZE_SPI_MSG_HEADER + 8) { + dev_err(dev, "SPI master cannot send large enough buffers, aborting\n"); + return -EINVAL; + } + + priv->max_xfer_len = SJA1105_SIZE_SPI_MSG_MAXLEN; + if (priv->max_xfer_len > max_xfer) + priv->max_xfer_len = max_xfer; + if (priv->max_xfer_len > max_msg - SJA1105_SIZE_SPI_MSG_HEADER) + priv->max_xfer_len = max_msg - SJA1105_SIZE_SPI_MSG_HEADER; + priv->info = of_device_get_match_data(dev); /* Detect hardware device */ diff --git a/drivers/net/dsa/sja1105/sja1105_spi.c b/drivers/net/dsa/sja1105/sja1105_spi.c index f7a1514f81e8..5a7b404bf3ce 100644 --- a/drivers/net/dsa/sja1105/sja1105_spi.c +++ b/drivers/net/dsa/sja1105/sja1105_spi.c @@ -8,8 +8,6 @@ #include "sja1105.h" #define SJA1105_SIZE_RESET_CMD 4 -#define SJA1105_SIZE_SPI_MSG_HEADER 4 -#define SJA1105_SIZE_SPI_MSG_MAXLEN (64 * 4) struct sja1105_chunk { u8 *buf; @@ -29,13 +27,6 @@ sja1105_spi_message_pack(void *buf, const struct sja1105_spi_message *msg) sja1105_pack(buf, &msg->address, 24, 4, size); } -#define sja1105_hdr_xfer(xfers, chunk) \ - ((xfers) + 2 * (chunk)) -#define sja1105_chunk_xfer(xfers, chunk) \ - ((xfers) + 2 * (chunk) + 1) -#define sja1105_hdr_buf(hdr_bufs, chunk) \ - ((hdr_bufs) + (chunk) * SJA1105_SIZE_SPI_MSG_HEADER) - /* If @rw is: * - SPI_WRITE: creates and sends an SPI write message at absolute * address reg_addr, taking @len bytes from *buf @@ -46,41 +37,25 @@ static int sja1105_xfer(const struct sja1105_private *priv, sja1105_spi_rw_mode_t rw, u64 reg_addr, u8 *buf, size_t len, struct ptp_system_timestamp *ptp_sts) { - struct sja1105_chunk chunk = { - .len = min_t(size_t, len, SJA1105_SIZE_SPI_MSG_MAXLEN), - .reg_addr = reg_addr, - .buf = buf, - }; + u8 hdr_buf[SJA1105_SIZE_SPI_MSG_HEADER] = {0}; struct spi_device *spi = priv->spidev; - struct spi_transfer *xfers; + struct spi_transfer xfers[2] = {0}; + struct spi_transfer *chunk_xfer; + struct spi_transfer *hdr_xfer; + struct sja1105_chunk chunk; int num_chunks; int rc, i = 0; - u8 *hdr_bufs; - num_chunks = DIV_ROUND_UP(len, SJA1105_SIZE_SPI_MSG_MAXLEN); + num_chunks = DIV_ROUND_UP(len, priv->max_xfer_len); - /* One transfer for each message header, one for each message - * payload (chunk). - */ - xfers = kcalloc(2 * num_chunks, sizeof(struct spi_transfer), - GFP_KERNEL); - if (!xfers) - return -ENOMEM; + chunk.reg_addr = reg_addr; + chunk.buf = buf; + chunk.len = min_t(size_t, len, priv->max_xfer_len); - /* Packed buffers for the num_chunks SPI message headers, - * stored as a contiguous array - */ - hdr_bufs = kcalloc(num_chunks, SJA1105_SIZE_SPI_MSG_HEADER, - GFP_KERNEL); - if (!hdr_bufs) { - kfree(xfers); - return -ENOMEM; - } + hdr_xfer = &xfers[0]; + chunk_xfer = &xfers[1]; for (i = 0; i < num_chunks; i++) { - struct spi_transfer *chunk_xfer = sja1105_chunk_xfer(xfers, i); - struct spi_transfer *hdr_xfer = sja1105_hdr_xfer(xfers, i); - u8 *hdr_buf = sja1105_hdr_buf(hdr_bufs, i); struct spi_transfer *ptp_sts_xfer; struct sja1105_spi_message msg; @@ -127,21 +102,16 @@ static int sja1105_xfer(const struct sja1105_private *priv, chunk.buf += chunk.len; chunk.reg_addr += chunk.len / 4; chunk.len = min_t(size_t, (ptrdiff_t)(buf + len - chunk.buf), - SJA1105_SIZE_SPI_MSG_MAXLEN); + priv->max_xfer_len); - /* De-assert the chip select after each chunk. */ - if (chunk.len) - chunk_xfer->cs_change = 1; + rc = spi_sync_transfer(spi, xfers, 2); + if (rc < 0) { + dev_err(&spi->dev, "SPI transfer failed: %d\n", rc); + return rc; + } } - rc = spi_sync_transfer(spi, xfers, 2 * num_chunks); - if (rc < 0) - dev_err(&spi->dev, "SPI transfer failed: %d\n", rc); - - kfree(hdr_bufs); - kfree(xfers); - - return rc; + return 0; } int sja1105_xfer_buf(const struct sja1105_private *priv, diff --git a/drivers/net/dsa/sja1105/sja1105_static_config.h b/drivers/net/dsa/sja1105/sja1105_static_config.h index bc7606899289..779eb6840f05 100644 --- a/drivers/net/dsa/sja1105/sja1105_static_config.h +++ b/drivers/net/dsa/sja1105/sja1105_static_config.h @@ -9,6 +9,8 @@ #include #include +#define SJA1105_SIZE_SPI_MSG_HEADER 4 +#define SJA1105_SIZE_SPI_MSG_MAXLEN (64 * 4) #define SJA1105_SIZE_DEVICE_ID 4 #define SJA1105_SIZE_TABLE_HEADER 12 #define SJA1105_SIZE_SCHEDULE_ENTRY 8