net: dsa: Introduce driver for NXP SJA1105 5-port L2 switch

At this moment the following is supported:
* Link state management through phylib
* Autonomous L2 forwarding managed through iproute2 bridge commands.

IP termination must be done currently through the master netdevice,
since the switch is unmanaged at this point and using
DSA_TAG_PROTO_NONE.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Georg Waibel <georg.waibel@sensor-technik.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 553 insertions, 0 deletions

diff --git a/drivers/net/dsa/sja1105/sja1105_spi.c b/drivers/net/dsa/sja1105/sja1105_spi.c
new file mode 100644
index 000000000000..07890bbf40f8
--- /dev/null
+++ b/drivers/net/dsa/sja1105/sja1105_spi.c
@@ -0,0 +1,553 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/* Copyright (c) 2016-2018, NXP Semiconductors
+ * Copyright (c) 2018, Sensor-Technik Wiedemann GmbH
+ * Copyright (c) 2018-2019, Vladimir Oltean <olteanv@gmail.com>
+ */
+#include <linux/spi/spi.h>
+#include <linux/packing.h>
+#include "sja1105.h"
+
+#define SJA1105_SIZE_RESET_CMD		4
+#define SJA1105_SIZE_SPI_MSG_HEADER	4
+#define SJA1105_SIZE_SPI_MSG_MAXLEN	(64 * 4)
+#define SJA1105_SIZE_SPI_TRANSFER_MAX	\
+	(SJA1105_SIZE_SPI_MSG_HEADER + SJA1105_SIZE_SPI_MSG_MAXLEN)
+
+static int sja1105_spi_transfer(const struct sja1105_private *priv,
+				const void *tx, void *rx, int size)
+{
+	struct spi_device *spi = priv->spidev;
+	struct spi_transfer transfer = {
+		.tx_buf = tx,
+		.rx_buf = rx,
+		.len = size,
+	};
+	struct spi_message msg;
+	int rc;
+
+	if (size > SJA1105_SIZE_SPI_TRANSFER_MAX) {
+		dev_err(&spi->dev, "SPI message (%d) longer than max of %d\n",
+			size, SJA1105_SIZE_SPI_TRANSFER_MAX);
+		return -EMSGSIZE;
+	}
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&transfer, &msg);
+
+	rc = spi_sync(spi, &msg);
+	if (rc < 0) {
+		dev_err(&spi->dev, "SPI transfer failed: %d\n", rc);
+		return rc;
+	}
+
+	return rc;
+}
+
+static void
+sja1105_spi_message_pack(void *buf, const struct sja1105_spi_message *msg)
+{
+	const int size = SJA1105_SIZE_SPI_MSG_HEADER;
+
+	memset(buf, 0, size);
+
+	sja1105_pack(buf, &msg->access,     31, 31, size);
+	sja1105_pack(buf, &msg->read_count, 30, 25, size);
+	sja1105_pack(buf, &msg->address,    24,  4, size);
+}
+
+/* If @rw is:
+ * - SPI_WRITE: creates and sends an SPI write message at absolute
+ *		address reg_addr, taking size_bytes from *packed_buf
+ * - SPI_READ:  creates and sends an SPI read message from absolute
+ *		address reg_addr, writing size_bytes into *packed_buf
+ *
+ * This function should only be called if it is priorly known that
+ * @size_bytes is smaller than SIZE_SPI_MSG_MAXLEN. Larger packed buffers
+ * are chunked in smaller pieces by sja1105_spi_send_long_packed_buf below.
+ */
+int sja1105_spi_send_packed_buf(const struct sja1105_private *priv,
+				sja1105_spi_rw_mode_t rw, u64 reg_addr,
+				void *packed_buf, size_t size_bytes)
+{
+	u8 tx_buf[SJA1105_SIZE_SPI_TRANSFER_MAX] = {0};
+	u8 rx_buf[SJA1105_SIZE_SPI_TRANSFER_MAX] = {0};
+	const int msg_len = size_bytes + SJA1105_SIZE_SPI_MSG_HEADER;
+	struct sja1105_spi_message msg = {0};
+	int rc;
+
+	if (msg_len > SJA1105_SIZE_SPI_TRANSFER_MAX)
+		return -ERANGE;
+
+	msg.access = rw;
+	msg.address = reg_addr;
+	if (rw == SPI_READ)
+		msg.read_count = size_bytes / 4;
+
+	sja1105_spi_message_pack(tx_buf, &msg);
+
+	if (rw == SPI_WRITE)
+		memcpy(tx_buf + SJA1105_SIZE_SPI_MSG_HEADER,
+		       packed_buf, size_bytes);
+
+	rc = sja1105_spi_transfer(priv, tx_buf, rx_buf, msg_len);
+	if (rc < 0)
+		return rc;
+
+	if (rw == SPI_READ)
+		memcpy(packed_buf, rx_buf + SJA1105_SIZE_SPI_MSG_HEADER,
+		       size_bytes);
+
+	return 0;
+}
+
+/* If @rw is:
+ * - SPI_WRITE: creates and sends an SPI write message at absolute
+ *		address reg_addr, taking size_bytes from *packed_buf
+ * - SPI_READ:  creates and sends an SPI read message from absolute
+ *		address reg_addr, writing size_bytes into *packed_buf
+ *
+ * The u64 *value is unpacked, meaning that it's stored in the native
+ * CPU endianness and directly usable by software running on the core.
+ *
+ * This is a wrapper around sja1105_spi_send_packed_buf().
+ */
+int sja1105_spi_send_int(const struct sja1105_private *priv,
+			 sja1105_spi_rw_mode_t rw, u64 reg_addr,
+			 u64 *value, u64 size_bytes)
+{
+	u8 packed_buf[SJA1105_SIZE_SPI_MSG_MAXLEN];
+	int rc;
+
+	if (size_bytes > SJA1105_SIZE_SPI_MSG_MAXLEN)
+		return -ERANGE;
+
+	if (rw == SPI_WRITE)
+		sja1105_pack(packed_buf, value, 8 * size_bytes - 1, 0,
+			     size_bytes);
+
+	rc = sja1105_spi_send_packed_buf(priv, rw, reg_addr, packed_buf,
+					 size_bytes);
+
+	if (rw == SPI_READ)
+		sja1105_unpack(packed_buf, value, 8 * size_bytes - 1, 0,
+			       size_bytes);
+
+	return rc;
+}
+
+/* Should be used if a @packed_buf larger than SJA1105_SIZE_SPI_MSG_MAXLEN
+ * must be sent/received. Splitting the buffer into chunks and assembling
+ * those into SPI messages is done automatically by this function.
+ */
+int sja1105_spi_send_long_packed_buf(const struct sja1105_private *priv,
+				     sja1105_spi_rw_mode_t rw, u64 base_addr,
+				     void *packed_buf, u64 buf_len)
+{
+	struct chunk {
+		void *buf_ptr;
+		int len;
+		u64 spi_address;
+	} chunk;
+	int distance_to_end;
+	int rc;
+
+	/* Initialize chunk */
+	chunk.buf_ptr = packed_buf;
+	chunk.spi_address = base_addr;
+	chunk.len = min_t(int, buf_len, SJA1105_SIZE_SPI_MSG_MAXLEN);
+
+	while (chunk.len) {
+		rc = sja1105_spi_send_packed_buf(priv, rw, chunk.spi_address,
+						 chunk.buf_ptr, chunk.len);
+		if (rc < 0)
+			return rc;
+
+		chunk.buf_ptr += chunk.len;
+		chunk.spi_address += chunk.len / 4;
+		distance_to_end = (uintptr_t)(packed_buf + buf_len -
+					      chunk.buf_ptr);
+		chunk.len = min(distance_to_end, SJA1105_SIZE_SPI_MSG_MAXLEN);
+	}
+
+	return 0;
+}
+
+/* Back-ported structure from UM11040 Table 112.
+ * Reset control register (addr. 100440h)
+ * In the SJA1105 E/T, only warm_rst and cold_rst are
+ * supported (exposed in UM10944 as rst_ctrl), but the bit
+ * offsets of warm_rst and cold_rst are actually reversed.
+ */
+struct sja1105_reset_cmd {
+	u64 switch_rst;
+	u64 cfg_rst;
+	u64 car_rst;
+	u64 otp_rst;
+	u64 warm_rst;
+	u64 cold_rst;
+	u64 por_rst;
+};
+
+static void
+sja1105et_reset_cmd_pack(void *buf, const struct sja1105_reset_cmd *reset)
+{
+	const int size = SJA1105_SIZE_RESET_CMD;
+
+	memset(buf, 0, size);
+
+	sja1105_pack(buf, &reset->cold_rst, 3, 3, size);
+	sja1105_pack(buf, &reset->warm_rst, 2, 2, size);
+}
+
+static void
+sja1105pqrs_reset_cmd_pack(void *buf, const struct sja1105_reset_cmd *reset)
+{
+	const int size = SJA1105_SIZE_RESET_CMD;
+
+	memset(buf, 0, size);
+
+	sja1105_pack(buf, &reset->switch_rst, 8, 8, size);
+	sja1105_pack(buf, &reset->cfg_rst,    7, 7, size);
+	sja1105_pack(buf, &reset->car_rst,    5, 5, size);
+	sja1105_pack(buf, &reset->otp_rst,    4, 4, size);
+	sja1105_pack(buf, &reset->warm_rst,   3, 3, size);
+	sja1105_pack(buf, &reset->cold_rst,   2, 2, size);
+	sja1105_pack(buf, &reset->por_rst,    1, 1, size);
+}
+
+static int sja1105et_reset_cmd(const void *ctx, const void *data)
+{
+	const struct sja1105_private *priv = ctx;
+	const struct sja1105_reset_cmd *reset = data;
+	const struct sja1105_regs *regs = priv->info->regs;
+	struct device *dev = priv->ds->dev;
+	u8 packed_buf[SJA1105_SIZE_RESET_CMD];
+
+	if (reset->switch_rst ||
+	    reset->cfg_rst ||
+	    reset->car_rst ||
+	    reset->otp_rst ||
+	    reset->por_rst) {
+		dev_err(dev, "Only warm and cold reset is supported "
+			"for SJA1105 E/T!\n");
+		return -EINVAL;
+	}
+
+	if (reset->warm_rst)
+		dev_dbg(dev, "Warm reset requested\n");
+	if (reset->cold_rst)
+		dev_dbg(dev, "Cold reset requested\n");
+
+	sja1105et_reset_cmd_pack(packed_buf, reset);
+
+	return sja1105_spi_send_packed_buf(priv, SPI_WRITE, regs->rgu,
+					   packed_buf, SJA1105_SIZE_RESET_CMD);
+}
+
+static int sja1105pqrs_reset_cmd(const void *ctx, const void *data)
+{
+	const struct sja1105_private *priv = ctx;
+	const struct sja1105_reset_cmd *reset = data;
+	const struct sja1105_regs *regs = priv->info->regs;
+	struct device *dev = priv->ds->dev;
+	u8 packed_buf[SJA1105_SIZE_RESET_CMD];
+
+	if (reset->switch_rst)
+		dev_dbg(dev, "Main reset for all functional modules requested\n");
+	if (reset->cfg_rst)
+		dev_dbg(dev, "Chip configuration reset requested\n");
+	if (reset->car_rst)
+		dev_dbg(dev, "Clock and reset control logic reset requested\n");
+	if (reset->otp_rst)
+		dev_dbg(dev, "OTP read cycle for reading product "
+			"config settings requested\n");
+	if (reset->warm_rst)
+		dev_dbg(dev, "Warm reset requested\n");
+	if (reset->cold_rst)
+		dev_dbg(dev, "Cold reset requested\n");
+	if (reset->por_rst)
+		dev_dbg(dev, "Power-on reset requested\n");
+
+	sja1105pqrs_reset_cmd_pack(packed_buf, reset);
+
+	return sja1105_spi_send_packed_buf(priv, SPI_WRITE, regs->rgu,
+					   packed_buf, SJA1105_SIZE_RESET_CMD);
+}
+
+static int sja1105_cold_reset(const struct sja1105_private *priv)
+{
+	struct sja1105_reset_cmd reset = {0};
+
+	reset.cold_rst = 1;
+	return priv->info->reset_cmd(priv, &reset);
+}
+
+struct sja1105_status {
+	u64 configs;
+	u64 crcchkl;
+	u64 ids;
+	u64 crcchkg;
+};
+
+/* This is not reading the entire General Status area, which is also
+ * divergent between E/T and P/Q/R/S, but only the relevant bits for
+ * ensuring that the static config upload procedure was successful.
+ */
+static void sja1105_status_unpack(void *buf, struct sja1105_status *status)
+{
+	/* So that addition translates to 4 bytes */
+	u32 *p = buf;
+
+	/* device_id is missing from the buffer, but we don't
+	 * want to diverge from the manual definition of the
+	 * register addresses, so we'll back off one step with
+	 * the register pointer, and never access p[0].
+	 */
+	p--;
+	sja1105_unpack(p + 0x1, &status->configs,   31, 31, 4);
+	sja1105_unpack(p + 0x1, &status->crcchkl,   30, 30, 4);
+	sja1105_unpack(p + 0x1, &status->ids,       29, 29, 4);
+	sja1105_unpack(p + 0x1, &status->crcchkg,   28, 28, 4);
+}
+
+static int sja1105_status_get(struct sja1105_private *priv,
+			      struct sja1105_status *status)
+{
+	const struct sja1105_regs *regs = priv->info->regs;
+	u8 packed_buf[4];
+	int rc;
+
+	rc = sja1105_spi_send_packed_buf(priv, SPI_READ,
+					 regs->status,
+					 packed_buf, 4);
+	if (rc < 0)
+		return rc;
+
+	sja1105_status_unpack(packed_buf, status);
+
+	return 0;
+}
+
+/* Not const because unpacking priv->static_config into buffers and preparing
+ * for upload requires the recalculation of table CRCs and updating the
+ * structures with these.
+ */
+static int
+static_config_buf_prepare_for_upload(struct sja1105_private *priv,
+				     void *config_buf, int buf_len)
+{
+	struct sja1105_static_config *config = &priv->static_config;
+	struct sja1105_table_header final_header;
+	sja1105_config_valid_t valid;
+	char *final_header_ptr;
+	int crc_len;
+
+	valid = sja1105_static_config_check_valid(config);
+	if (valid != SJA1105_CONFIG_OK) {
+		dev_err(&priv->spidev->dev,
+			sja1105_static_config_error_msg[valid]);
+		return -EINVAL;
+	}
+
+	/* Write Device ID and config tables to config_buf */
+	sja1105_static_config_pack(config_buf, config);
+	/* Recalculate CRC of the last header (right now 0xDEADBEEF).
+	 * Don't include the CRC field itself.
+	 */
+	crc_len = buf_len - 4;
+	/* Read the whole table header */
+	final_header_ptr = config_buf + buf_len - SJA1105_SIZE_TABLE_HEADER;
+	sja1105_table_header_packing(final_header_ptr, &final_header, UNPACK);
+	/* Modify */
+	final_header.crc = sja1105_crc32(config_buf, crc_len);
+	/* Rewrite */
+	sja1105_table_header_packing(final_header_ptr, &final_header, PACK);
+
+	return 0;
+}
+
+#define RETRIES 10
+
+int sja1105_static_config_upload(struct sja1105_private *priv)
+{
+	struct sja1105_static_config *config = &priv->static_config;
+	const struct sja1105_regs *regs = priv->info->regs;
+	struct device *dev = &priv->spidev->dev;
+	struct sja1105_status status;
+	int rc, retries = RETRIES;
+	u8 *config_buf;
+	int buf_len;
+
+	buf_len = sja1105_static_config_get_length(config);
+	config_buf = kcalloc(buf_len, sizeof(char), GFP_KERNEL);
+	if (!config_buf)
+		return -ENOMEM;
+
+	rc = static_config_buf_prepare_for_upload(priv, config_buf, buf_len);
+	if (rc < 0) {
+		dev_err(dev, "Invalid config, cannot upload\n");
+		return -EINVAL;
+	}
+	do {
+		/* Put the SJA1105 in programming mode */
+		rc = sja1105_cold_reset(priv);
+		if (rc < 0) {
+			dev_err(dev, "Failed to reset switch, retrying...\n");
+			continue;
+		}
+		/* Wait for the switch to come out of reset */
+		usleep_range(1000, 5000);
+		/* Upload the static config to the device */
+		rc = sja1105_spi_send_long_packed_buf(priv, SPI_WRITE,
+						      regs->config,
+						      config_buf, buf_len);
+		if (rc < 0) {
+			dev_err(dev, "Failed to upload config, retrying...\n");
+			continue;
+		}
+		/* Check that SJA1105 responded well to the config upload */
+		rc = sja1105_status_get(priv, &status);
+		if (rc < 0)
+			continue;
+
+		if (status.ids == 1) {
+			dev_err(dev, "Mismatch between hardware and static config "
+				"device id. Wrote 0x%llx, wants 0x%llx\n",
+				config->device_id, priv->info->device_id);
+			continue;
+		}
+		if (status.crcchkl == 1) {
+			dev_err(dev, "Switch reported invalid local CRC on "
+				"the uploaded config, retrying...\n");
+			continue;
+		}
+		if (status.crcchkg == 1) {
+			dev_err(dev, "Switch reported invalid global CRC on "
+				"the uploaded config, retrying...\n");
+			continue;
+		}
+		if (status.configs == 0) {
+			dev_err(dev, "Switch reported that configuration is "
+				"invalid, retrying...\n");
+			continue;
+		}
+	} while (--retries && (status.crcchkl == 1 || status.crcchkg == 1 ||
+		 status.configs == 0 || status.ids == 1));
+
+	if (!retries) {
+		rc = -EIO;
+		dev_err(dev, "Failed to upload config to device, giving up\n");
+		goto out;
+	} else if (retries != RETRIES - 1) {
+		dev_info(dev, "Succeeded after %d tried\n", RETRIES - retries);
+	}
+
+	dev_info(dev, "Reset switch and programmed static config\n");
+out:
+	kfree(config_buf);
+	return rc;
+}
+
+struct sja1105_regs sja1105et_regs = {
+	.device_id = 0x0,
+	.prod_id = 0x100BC3,
+	.status = 0x1,
+	.config = 0x020000,
+	.rgu = 0x100440,
+	.pad_mii_tx = {0x100800, 0x100802, 0x100804, 0x100806, 0x100808},
+	.rmii_pll1 = 0x10000A,
+	.cgu_idiv = {0x10000B, 0x10000C, 0x10000D, 0x10000E, 0x10000F},
+	/* UM10944.pdf, Table 86, ACU Register overview */
+	.rgmii_pad_mii_tx = {0x100800, 0x100802, 0x100804, 0x100806, 0x100808},
+	.mac = {0x200, 0x202, 0x204, 0x206, 0x208},
+	.mac_hl1 = {0x400, 0x410, 0x420, 0x430, 0x440},
+	.mac_hl2 = {0x600, 0x610, 0x620, 0x630, 0x640},
+	/* UM10944.pdf, Table 78, CGU Register overview */
+	.mii_tx_clk = {0x100013, 0x10001A, 0x100021, 0x100028, 0x10002F},
+	.mii_rx_clk = {0x100014, 0x10001B, 0x100022, 0x100029, 0x100030},
+	.mii_ext_tx_clk = {0x100018, 0x10001F, 0x100026, 0x10002D, 0x100034},
+	.mii_ext_rx_clk = {0x100019, 0x100020, 0x100027, 0x10002E, 0x100035},
+	.rgmii_tx_clk = {0x100016, 0x10001D, 0x100024, 0x10002B, 0x100032},
+	.rmii_ref_clk = {0x100015, 0x10001C, 0x100023, 0x10002A, 0x100031},
+	.rmii_ext_tx_clk = {0x100018, 0x10001F, 0x100026, 0x10002D, 0x100034},
+};
+
+struct sja1105_regs sja1105pqrs_regs = {
+	.device_id = 0x0,
+	.prod_id = 0x100BC3,
+	.status = 0x1,
+	.config = 0x020000,
+	.rgu = 0x100440,
+	.pad_mii_tx = {0x100800, 0x100802, 0x100804, 0x100806, 0x100808},
+	.rmii_pll1 = 0x10000A,
+	.cgu_idiv = {0x10000B, 0x10000C, 0x10000D, 0x10000E, 0x10000F},
+	/* UM10944.pdf, Table 86, ACU Register overview */
+	.rgmii_pad_mii_tx = {0x100800, 0x100802, 0x100804, 0x100806, 0x100808},
+	.mac = {0x200, 0x202, 0x204, 0x206, 0x208},
+	.mac_hl1 = {0x400, 0x410, 0x420, 0x430, 0x440},
+	.mac_hl2 = {0x600, 0x610, 0x620, 0x630, 0x640},
+	/* UM11040.pdf, Table 114 */
+	.mii_tx_clk = {0x100013, 0x100019, 0x10001F, 0x100025, 0x10002B},
+	.mii_rx_clk = {0x100014, 0x10001A, 0x100020, 0x100026, 0x10002C},
+	.mii_ext_tx_clk = {0x100017, 0x10001D, 0x100023, 0x100029, 0x10002F},
+	.mii_ext_rx_clk = {0x100018, 0x10001E, 0x100024, 0x10002A, 0x100030},
+	.rgmii_tx_clk = {0x100016, 0x10001C, 0x100022, 0x100028, 0x10002E},
+	.rmii_ref_clk = {0x100015, 0x10001B, 0x100021, 0x100027, 0x10002D},
+	.rmii_ext_tx_clk = {0x100017, 0x10001D, 0x100023, 0x100029, 0x10002F},
+	.qlevel = {0x604, 0x614, 0x624, 0x634, 0x644},
+};
+
+struct sja1105_info sja1105e_info = {
+	.device_id		= SJA1105E_DEVICE_ID,
+	.part_no		= SJA1105ET_PART_NO,
+	.static_ops		= sja1105e_table_ops,
+	.dyn_ops		= sja1105et_dyn_ops,
+	.reset_cmd		= sja1105et_reset_cmd,
+	.regs			= &sja1105et_regs,
+	.name			= "SJA1105E",
+};
+struct sja1105_info sja1105t_info = {
+	.device_id		= SJA1105T_DEVICE_ID,
+	.part_no		= SJA1105ET_PART_NO,
+	.static_ops		= sja1105t_table_ops,
+	.dyn_ops		= sja1105et_dyn_ops,
+	.reset_cmd		= sja1105et_reset_cmd,
+	.regs			= &sja1105et_regs,
+	.name			= "SJA1105T",
+};
+struct sja1105_info sja1105p_info = {
+	.device_id		= SJA1105PR_DEVICE_ID,
+	.part_no		= SJA1105P_PART_NO,
+	.static_ops		= sja1105p_table_ops,
+	.dyn_ops		= sja1105pqrs_dyn_ops,
+	.reset_cmd		= sja1105pqrs_reset_cmd,
+	.regs			= &sja1105pqrs_regs,
+	.name			= "SJA1105P",
+};
+struct sja1105_info sja1105q_info = {
+	.device_id		= SJA1105QS_DEVICE_ID,
+	.part_no		= SJA1105Q_PART_NO,
+	.static_ops		= sja1105q_table_ops,
+	.dyn_ops		= sja1105pqrs_dyn_ops,
+	.reset_cmd		= sja1105pqrs_reset_cmd,
+	.regs			= &sja1105pqrs_regs,
+	.name			= "SJA1105Q",
+};
+struct sja1105_info sja1105r_info = {
+	.device_id		= SJA1105PR_DEVICE_ID,
+	.part_no		= SJA1105R_PART_NO,
+	.static_ops		= sja1105r_table_ops,
+	.dyn_ops		= sja1105pqrs_dyn_ops,
+	.reset_cmd		= sja1105pqrs_reset_cmd,
+	.regs			= &sja1105pqrs_regs,
+	.name			= "SJA1105R",
+};
+struct sja1105_info sja1105s_info = {
+	.device_id		= SJA1105QS_DEVICE_ID,
+	.part_no		= SJA1105S_PART_NO,
+	.static_ops		= sja1105s_table_ops,
+	.dyn_ops		= sja1105pqrs_dyn_ops,
+	.regs			= &sja1105pqrs_regs,
+	.reset_cmd		= sja1105pqrs_reset_cmd,
+	.name			= "SJA1105S",
+};