Merge branch 'mlxsw-use-MRSR-register-for-FW-reset'

Ido Schimmel says:

====================
mlxsw: use MRSR register for FW reset

Jiri says:

Introduce a MRSR register definition and use it to do FW reset instead
of existing mechanism using PCI BAR0 register.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/cmd.h

@@ -58,7 +58,7 @@ static inline void mlxsw_cmd_mbox_zero(char *mbox)
 struct mlxsw_core;
 
 int mlxsw_cmd_exec(struct mlxsw_core *mlxsw_core, u16 opcode, u8 opcode_mod,
-		   u32 in_mod, bool out_mbox_direct,
+		   u32 in_mod, bool out_mbox_direct, bool reset_ok,
 		   char *in_mbox, size_t in_mbox_size,
 		   char *out_mbox, size_t out_mbox_size);
 
@@ -67,7 +67,7 @@ static inline int mlxsw_cmd_exec_in(struct mlxsw_core *mlxsw_core, u16 opcode,
 				    size_t in_mbox_size)
 {
 	return mlxsw_cmd_exec(mlxsw_core, opcode, opcode_mod, in_mod, false,
-			      in_mbox, in_mbox_size, NULL, 0);
+			      false, in_mbox, in_mbox_size, NULL, 0);
 }
 
 static inline int mlxsw_cmd_exec_out(struct mlxsw_core *mlxsw_core, u16 opcode,
@@ -76,7 +76,7 @@ static inline int mlxsw_cmd_exec_out(struct mlxsw_core *mlxsw_core, u16 opcode,
 				     char *out_mbox, size_t out_mbox_size)
 {
 	return mlxsw_cmd_exec(mlxsw_core, opcode, opcode_mod, in_mod,
-			      out_mbox_direct, NULL, 0,
+			      out_mbox_direct, false, NULL, 0,
 			      out_mbox, out_mbox_size);
 }
 
@@ -84,7 +84,7 @@ static inline int mlxsw_cmd_exec_none(struct mlxsw_core *mlxsw_core, u16 opcode,
 				      u8 opcode_mod, u32 in_mod)
 {
 	return mlxsw_cmd_exec(mlxsw_core, opcode, opcode_mod, in_mod, false,
-			      NULL, 0, NULL, 0);
+			      false, NULL, 0, NULL, 0);
 }
 
 enum mlxsw_cmd_opcode {
@@ -179,6 +179,8 @@ enum mlxsw_cmd_status {
 	MLXSW_CMD_STATUS_BAD_INDEX	= 0x0A,
 	/* NVMEM checksum/CRC failed. */
 	MLXSW_CMD_STATUS_BAD_NVMEM	= 0x0B,
+	/* Device is currently running reset */
+	MLXSW_CMD_STATUS_RUNNING_RESET	= 0x26,
 	/* Bad management packet (silently discarded). */
 	MLXSW_CMD_STATUS_BAD_PKT	= 0x30,
 };
@@ -208,6 +210,8 @@ static inline const char *mlxsw_cmd_status_str(u8 status)
 		return "BAD_INDEX";
 	case MLXSW_CMD_STATUS_BAD_NVMEM:
 		return "BAD_NVMEM";
+	case MLXSW_CMD_STATUS_RUNNING_RESET:
+		return "RUNNING_RESET";
 	case MLXSW_CMD_STATUS_BAD_PKT:
 		return "BAD_PKT";
 	default:
@@ -869,10 +873,12 @@ MLXSW_ITEM32(cmd_mbox, config_profile, cqe_version, 0xB0, 0, 8);
  */
 
 static inline int mlxsw_cmd_access_reg(struct mlxsw_core *mlxsw_core,
+				       bool reset_ok,
 				       char *in_mbox, char *out_mbox)
 {
 	return mlxsw_cmd_exec(mlxsw_core, MLXSW_CMD_OPCODE_ACCESS_REG,
-			      0, 0, false, in_mbox, MLXSW_CMD_MBOX_SIZE,
+			      0, 0, false, reset_ok,
+			      in_mbox, MLXSW_CMD_MBOX_SIZE,
 			      out_mbox, MLXSW_CMD_MBOX_SIZE);
 }
 

drivers/net/ethernet/mellanox/mlxsw/core.c

@@ -966,14 +966,12 @@ mlxsw_devlink_sb_occ_tc_port_bind_get(struct devlink_port *devlink_port,
 static int mlxsw_devlink_core_bus_device_reload(struct devlink *devlink)
 {
 	struct mlxsw_core *mlxsw_core = devlink_priv(devlink);
-	const struct mlxsw_bus *mlxsw_bus = mlxsw_core->bus;
 	int err;
 
-	if (!mlxsw_bus->reset)
+	if (!(mlxsw_core->bus->features & MLXSW_BUS_F_RESET))
 		return -EOPNOTSUPP;
 
 	mlxsw_core_bus_device_unregister(mlxsw_core, true);
-	mlxsw_bus->reset(mlxsw_core->bus_priv);
 	err = mlxsw_core_bus_device_register(mlxsw_core->bus_info,
 					     mlxsw_core->bus,
 					     mlxsw_core->bus_priv, true,
@@ -1480,6 +1478,7 @@ static int mlxsw_core_reg_access_cmd(struct mlxsw_core *mlxsw_core,
 {
 	enum mlxsw_emad_op_tlv_status status;
 	int err, n_retry;
+	bool reset_ok;
 	char *in_mbox, *out_mbox, *tmp;
 
 	dev_dbg(mlxsw_core->bus_info->dev, "Reg cmd access (reg_id=%x(%s),type=%s)\n",
@@ -1501,9 +1500,16 @@ static int mlxsw_core_reg_access_cmd(struct mlxsw_core *mlxsw_core,
 	tmp = in_mbox + MLXSW_EMAD_OP_TLV_LEN * sizeof(u32);
 	mlxsw_emad_pack_reg_tlv(tmp, reg, payload);
 
+	/* There is a special treatment needed for MRSR (reset) register.
+	 * The command interface will return error after the command
+	 * is executed, so tell the lower layer to expect it
+	 * and cope accordingly.
+	 */
+	reset_ok = reg->id == MLXSW_REG_MRSR_ID;
+
 	n_retry = 0;
 retry:
-	err = mlxsw_cmd_access_reg(mlxsw_core, in_mbox, out_mbox);
+	err = mlxsw_cmd_access_reg(mlxsw_core, reset_ok, in_mbox, out_mbox);
 	if (!err) {
 		err = mlxsw_emad_process_status(out_mbox, &status);
 		if (err) {
@@ -1793,7 +1799,7 @@ static void mlxsw_core_buf_dump_dbg(struct mlxsw_core *mlxsw_core,
 }
 
 int mlxsw_cmd_exec(struct mlxsw_core *mlxsw_core, u16 opcode, u8 opcode_mod,
-		   u32 in_mod, bool out_mbox_direct,
+		   u32 in_mod, bool out_mbox_direct, bool reset_ok,
 		   char *in_mbox, size_t in_mbox_size,
 		   char *out_mbox, size_t out_mbox_size)
 {
@@ -1816,7 +1822,15 @@ int mlxsw_cmd_exec(struct mlxsw_core *mlxsw_core, u16 opcode, u8 opcode_mod,
 					in_mbox, in_mbox_size,
 					out_mbox, out_mbox_size, &status);
 
-	if (err == -EIO && status != MLXSW_CMD_STATUS_OK) {
+	if (!err && out_mbox) {
+		dev_dbg(mlxsw_core->bus_info->dev, "Output mailbox:\n");
+		mlxsw_core_buf_dump_dbg(mlxsw_core, out_mbox, out_mbox_size);
+	}
+
+	if (reset_ok && err == -EIO &&
+	    status == MLXSW_CMD_STATUS_RUNNING_RESET) {
+		err = 0;
+	} else if (err == -EIO && status != MLXSW_CMD_STATUS_OK) {
 		dev_err(mlxsw_core->bus_info->dev, "Cmd exec failed (opcode=%x(%s),opcode_mod=%x,in_mod=%x,status=%x(%s))\n",
 			opcode, mlxsw_cmd_opcode_str(opcode), opcode_mod,
 			in_mod, status, mlxsw_cmd_status_str(status));
@@ -1826,10 +1840,6 @@ int mlxsw_cmd_exec(struct mlxsw_core *mlxsw_core, u16 opcode, u8 opcode_mod,
 			in_mod);
 	}
 
-	if (!err && out_mbox) {
-		dev_dbg(mlxsw_core->bus_info->dev, "Output mailbox:\n");
-		mlxsw_core_buf_dump_dbg(mlxsw_core, out_mbox, out_mbox_size);
-	}
 	return err;
 }
 EXPORT_SYMBOL(mlxsw_cmd_exec);

drivers/net/ethernet/mellanox/mlxsw/core.h

@@ -337,6 +337,7 @@ u64 mlxsw_core_res_get(struct mlxsw_core *mlxsw_core,
 	mlxsw_core_res_get(mlxsw_core, MLXSW_RES_ID_##short_res_id)
 
 #define MLXSW_BUS_F_TXRX	BIT(0)
+#define MLXSW_BUS_F_RESET	BIT(1)
 
 struct mlxsw_bus {
 	const char *kind;
@@ -344,7 +345,6 @@ struct mlxsw_bus {
 		    const struct mlxsw_config_profile *profile,
 		    struct mlxsw_res *res);
 	void (*fini)(void *bus_priv);
-	void (*reset)(void *bus_priv);
 	bool (*skb_transmit_busy)(void *bus_priv,
 				  const struct mlxsw_tx_info *tx_info);
 	int (*skb_transmit)(void *bus_priv, struct sk_buff *skb,

drivers/net/ethernet/mellanox/mlxsw/pci.c

@@ -1371,6 +1371,51 @@ static void mlxsw_pci_mbox_free(struct mlxsw_pci *mlxsw_pci,
 			    mbox->mapaddr);
 }
 
+static int mlxsw_pci_sw_reset(struct mlxsw_pci *mlxsw_pci,
+			      const struct pci_device_id *id)
+{
+	unsigned long end;
+	char mrsr_pl[MLXSW_REG_MRSR_LEN];
+	int err;
+
+	mlxsw_reg_mrsr_pack(mrsr_pl);
+	err = mlxsw_reg_write(mlxsw_pci->core, MLXSW_REG(mrsr), mrsr_pl);
+	if (err)
+		return err;
+	if (id->device == PCI_DEVICE_ID_MELLANOX_SWITCHX2) {
+		msleep(MLXSW_PCI_SW_RESET_TIMEOUT_MSECS);
+		return 0;
+	}
+
+	/* We must wait for the HW to become responsive once again. */
+	msleep(MLXSW_PCI_SW_RESET_WAIT_MSECS);
+
+	end = jiffies + msecs_to_jiffies(MLXSW_PCI_SW_RESET_TIMEOUT_MSECS);
+	do {
+		u32 val = mlxsw_pci_read32(mlxsw_pci, FW_READY);
+
+		if ((val & MLXSW_PCI_FW_READY_MASK) == MLXSW_PCI_FW_READY_MAGIC)
+			break;
+		cond_resched();
+	} while (time_before(jiffies, end));
+	return 0;
+}
+
+static int mlxsw_pci_alloc_irq_vectors(struct mlxsw_pci *mlxsw_pci)
+{
+	int err;
+
+	err = pci_alloc_irq_vectors(mlxsw_pci->pdev, 1, 1, PCI_IRQ_MSIX);
+	if (err < 0)
+		dev_err(&mlxsw_pci->pdev->dev, "MSI-X init failed\n");
+	return err;
+}
+
+static void mlxsw_pci_free_irq_vectors(struct mlxsw_pci *mlxsw_pci)
+{
+	pci_free_irq_vectors(mlxsw_pci->pdev);
+}
+
 static int mlxsw_pci_init(void *bus_priv, struct mlxsw_core *mlxsw_core,
 			  const struct mlxsw_config_profile *profile,
 			  struct mlxsw_res *res)
@@ -1398,6 +1443,16 @@ static int mlxsw_pci_init(void *bus_priv, struct mlxsw_core *mlxsw_core,
 	if (err)
 		goto err_out_mbox_alloc;
 
+	err = mlxsw_pci_sw_reset(mlxsw_pci, mlxsw_pci->id);
+	if (err)
+		goto err_sw_reset;
+
+	err = mlxsw_pci_alloc_irq_vectors(mlxsw_pci);
+	if (err < 0) {
+		dev_err(&pdev->dev, "MSI-X init failed\n");
+		goto err_alloc_irq;
+	}
+
 	err = mlxsw_cmd_query_fw(mlxsw_core, mbox);
 	if (err)
 		goto err_query_fw;
@@ -1481,6 +1536,9 @@ static int mlxsw_pci_init(void *bus_priv, struct mlxsw_core *mlxsw_core,
 err_doorbell_page_bar:
 err_iface_rev:
 err_query_fw:
+	mlxsw_pci_free_irq_vectors(mlxsw_pci);
+err_alloc_irq:
+err_sw_reset:
 	mlxsw_pci_mbox_free(mlxsw_pci, &mlxsw_pci->cmd.out_mbox);
 err_out_mbox_alloc:
 	mlxsw_pci_mbox_free(mlxsw_pci, &mlxsw_pci->cmd.in_mbox);
@@ -1496,6 +1554,7 @@ static void mlxsw_pci_fini(void *bus_priv)
 	free_irq(pci_irq_vector(mlxsw_pci->pdev, 0), mlxsw_pci);
 	mlxsw_pci_aqs_fini(mlxsw_pci);
 	mlxsw_pci_fw_area_fini(mlxsw_pci);
+	mlxsw_pci_free_irq_vectors(mlxsw_pci);
 	mlxsw_pci_mbox_free(mlxsw_pci, &mlxsw_pci->cmd.out_mbox);
 	mlxsw_pci_mbox_free(mlxsw_pci, &mlxsw_pci->cmd.in_mbox);
 }
@@ -1677,58 +1736,6 @@ static int mlxsw_pci_cmd_exec(void *bus_priv, u16 opcode, u8 opcode_mod,
 	return err;
 }
 
-static int mlxsw_pci_sw_reset(struct mlxsw_pci *mlxsw_pci,
-			      const struct pci_device_id *id)
-{
-	unsigned long end;
-
-	mlxsw_pci_write32(mlxsw_pci, SW_RESET, MLXSW_PCI_SW_RESET_RST_BIT);
-	if (id->device == PCI_DEVICE_ID_MELLANOX_SWITCHX2) {
-		msleep(MLXSW_PCI_SW_RESET_TIMEOUT_MSECS);
-		return 0;
-	}
-
-	/* Reset needs to be written before we read control register, and
-	 * we must wait for the HW to become responsive once again
-	 */
-	wmb();
-	msleep(MLXSW_PCI_SW_RESET_WAIT_MSECS);
-
-	end = jiffies + msecs_to_jiffies(MLXSW_PCI_SW_RESET_TIMEOUT_MSECS);
-	do {
-		u32 val = mlxsw_pci_read32(mlxsw_pci, FW_READY);
-
-		if ((val & MLXSW_PCI_FW_READY_MASK) == MLXSW_PCI_FW_READY_MAGIC)
-			break;
-		cond_resched();
-	} while (time_before(jiffies, end));
-	return 0;
-}
-
-static void mlxsw_pci_free_irq_vectors(struct mlxsw_pci *mlxsw_pci)
-{
-	pci_free_irq_vectors(mlxsw_pci->pdev);
-}
-
-static int mlxsw_pci_alloc_irq_vectors(struct mlxsw_pci *mlxsw_pci)
-{
-	int err;
-
-	err = pci_alloc_irq_vectors(mlxsw_pci->pdev, 1, 1, PCI_IRQ_MSIX);
-	if (err < 0)
-		dev_err(&mlxsw_pci->pdev->dev, "MSI-X init failed\n");
-	return err;
-}
-
-static void mlxsw_pci_reset(void *bus_priv)
-{
-	struct mlxsw_pci *mlxsw_pci = bus_priv;
-
-	mlxsw_pci_free_irq_vectors(mlxsw_pci);
-	mlxsw_pci_sw_reset(mlxsw_pci, mlxsw_pci->id);
-	mlxsw_pci_alloc_irq_vectors(mlxsw_pci);
-}
-
 static const struct mlxsw_bus mlxsw_pci_bus = {
 	.kind			= "pci",
 	.init			= mlxsw_pci_init,
@@ -1736,8 +1743,7 @@ static const struct mlxsw_bus mlxsw_pci_bus = {
 	.skb_transmit_busy	= mlxsw_pci_skb_transmit_busy,
 	.skb_transmit		= mlxsw_pci_skb_transmit,
 	.cmd_exec		= mlxsw_pci_cmd_exec,
-	.features		= MLXSW_BUS_F_TXRX,
-	.reset			= mlxsw_pci_reset,
+	.features		= MLXSW_BUS_F_TXRX | MLXSW_BUS_F_RESET,
 };
 
 static int mlxsw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
@@ -1795,18 +1801,6 @@ static int mlxsw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	mlxsw_pci->pdev = pdev;
 	pci_set_drvdata(pdev, mlxsw_pci);
 
-	err = mlxsw_pci_sw_reset(mlxsw_pci, id);
-	if (err) {
-		dev_err(&pdev->dev, "Software reset failed\n");
-		goto err_sw_reset;
-	}
-
-	err = mlxsw_pci_alloc_irq_vectors(mlxsw_pci);
-	if (err < 0) {
-		dev_err(&pdev->dev, "MSI-X init failed\n");
-		goto err_msix_init;
-	}
-
 	mlxsw_pci->bus_info.device_kind = driver_name;
 	mlxsw_pci->bus_info.device_name = pci_name(mlxsw_pci->pdev);
 	mlxsw_pci->bus_info.dev = &pdev->dev;
@@ -1823,9 +1817,6 @@ static int mlxsw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	return 0;
 
 err_bus_device_register:
-	mlxsw_pci_free_irq_vectors(mlxsw_pci);
-err_msix_init:
-err_sw_reset:
 	iounmap(mlxsw_pci->hw_addr);
 err_ioremap:
 err_pci_resource_len_check:
@@ -1843,7 +1834,6 @@ static void mlxsw_pci_remove(struct pci_dev *pdev)
 	struct mlxsw_pci *mlxsw_pci = pci_get_drvdata(pdev);
 
 	mlxsw_core_bus_device_unregister(mlxsw_pci->core, false);
-	mlxsw_pci_free_irq_vectors(mlxsw_pci);
 	iounmap(mlxsw_pci->hw_addr);
 	pci_release_regions(mlxsw_pci->pdev);
 	pci_disable_device(mlxsw_pci->pdev);

drivers/net/ethernet/mellanox/mlxsw/reg.h

@@ -7034,6 +7034,30 @@ static inline void mlxsw_reg_mpar_pack(char *payload, u8 local_port,
 	mlxsw_reg_mpar_pa_id_set(payload, pa_id);
 }
 
+/* MRSR - Management Reset and Shutdown Register
+ * ---------------------------------------------
+ * MRSR register is used to reset or shutdown the switch or
+ * the entire system (when applicable).
+ */
+#define MLXSW_REG_MRSR_ID 0x9023
+#define MLXSW_REG_MRSR_LEN 0x08
+
+MLXSW_REG_DEFINE(mrsr, MLXSW_REG_MRSR_ID, MLXSW_REG_MRSR_LEN);
+
+/* reg_mrsr_command
+ * Reset/shutdown command
+ * 0 - do nothing
+ * 1 - software reset
+ * Access: WO
+ */
+MLXSW_ITEM32(reg, mrsr, command, 0x00, 0, 4);
+
+static inline void mlxsw_reg_mrsr_pack(char *payload)
+{
+	MLXSW_REG_ZERO(mrsr, payload);
+	mlxsw_reg_mrsr_command_set(payload, 1);
+}
+
 /* MLCR - Management LED Control Register
  * --------------------------------------
  * Controls the system LEDs.
@@ -7898,6 +7922,7 @@ static const struct mlxsw_reg_info *mlxsw_reg_infos[] = {
 	MLXSW_REG(mcia),
 	MLXSW_REG(mpat),
 	MLXSW_REG(mpar),
+	MLXSW_REG(mrsr),
 	MLXSW_REG(mlcr),
 	MLXSW_REG(mpsc),
 	MLXSW_REG(mcqi),