sfc: Make MCDI independent of Siena

Move the lowest layer (transport) of the current MCDI code to
per-NIC-type operations.

Introduce a new structure and efx_nic member for MCDI-specific data.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/sfc/mcdi.c

@@ -24,13 +24,6 @@
 
 #define MCDI_RPC_TIMEOUT       (10 * HZ)
 
-#define MCDI_PDU(efx)							\
-	(efx_port_num(efx) ? MC_SMEM_P1_PDU_OFST : MC_SMEM_P0_PDU_OFST)
-#define MCDI_DOORBELL(efx)						\
-	(efx_port_num(efx) ? MC_SMEM_P1_DOORBELL_OFST : MC_SMEM_P0_DOORBELL_OFST)
-#define MCDI_STATUS(efx)						\
-	(efx_port_num(efx) ? MC_SMEM_P1_STATUS_OFST : MC_SMEM_P0_STATUS_OFST)
-
 /* A reboot/assertion causes the MCDI status word to be set after the
  * command word is set or a REBOOT event is sent. If we notice a reboot
  * via these mechanisms then wait 10ms for the status word to be set. */
@@ -44,16 +37,18 @@
 
 static inline struct efx_mcdi_iface *efx_mcdi(struct efx_nic *efx)
 {
-	struct siena_nic_data *nic_data;
-	EFX_BUG_ON_PARANOID(efx_nic_rev(efx) < EFX_REV_SIENA_A0);
-	nic_data = efx->nic_data;
-	return &nic_data->mcdi;
+	EFX_BUG_ON_PARANOID(!efx->mcdi);
+	return &efx->mcdi->iface;
 }
 
 int efx_mcdi_init(struct efx_nic *efx)
 {
 	struct efx_mcdi_iface *mcdi;
 
+	efx->mcdi = kzalloc(sizeof(*efx->mcdi), GFP_KERNEL);
+	if (!efx->mcdi)
+		return -ENOMEM;
+
 	mcdi = efx_mcdi(efx);
 	init_waitqueue_head(&mcdi->wq);
 	spin_lock_init(&mcdi->iface_lock);
@@ -66,16 +61,19 @@ int efx_mcdi_init(struct efx_nic *efx)
 	return efx_mcdi_handle_assertion(efx);
 }
 
+void efx_mcdi_fini(struct efx_nic *efx)
+{
+	BUG_ON(efx->mcdi &&
+	       atomic_read(&efx->mcdi->iface.state) != MCDI_STATE_QUIESCENT);
+	kfree(efx->mcdi);
+}
+
 static void efx_mcdi_copyin(struct efx_nic *efx, unsigned cmd,
 			    const efx_dword_t *inbuf, size_t inlen)
 {
 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
-	unsigned pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
-	unsigned doorbell = FR_CZ_MC_TREG_SMEM + MCDI_DOORBELL(efx);
-	unsigned int i;
 	efx_dword_t hdr;
 	u32 xflags, seqno;
-	unsigned int inlen_dw = DIV_ROUND_UP(inlen, 4);
 
 	BUG_ON(atomic_read(&mcdi->state) == MCDI_STATE_QUIESCENT);
 	BUG_ON(inlen > MCDI_CTL_SDU_LEN_MAX_V1);
@@ -93,31 +91,18 @@ static void efx_mcdi_copyin(struct efx_nic *efx, unsigned cmd,
 			     MCDI_HEADER_SEQ, seqno,
 			     MCDI_HEADER_XFLAGS, xflags);
 
-	efx_writed(efx, &hdr, pdu);
-
-	for (i = 0; i < inlen_dw; i++)
-		efx_writed(efx, &inbuf[i], pdu + 4 + 4 * i);
-
-	/* Ensure the payload is written out before the header */
-	wmb();
-
-	/* ring the doorbell with a distinctive value */
-	_efx_writed(efx, (__force __le32) 0x45789abc, doorbell);
+	efx->type->mcdi_request(efx, &hdr, 4, inbuf, inlen);
 }
 
 static void
 efx_mcdi_copyout(struct efx_nic *efx, efx_dword_t *outbuf, size_t outlen)
 {
 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
-	unsigned int pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
-	unsigned int outlen_dw = DIV_ROUND_UP(outlen, 4);
-	int i;
 
 	BUG_ON(atomic_read(&mcdi->state) == MCDI_STATE_QUIESCENT);
 	BUG_ON(outlen > MCDI_CTL_SDU_LEN_MAX_V1);
 
-	for (i = 0; i < outlen_dw; i++)
-		efx_readd(efx, &outbuf[i], pdu + 4 + 4 * i);
+	efx->type->mcdi_read_response(efx, outbuf, 4, outlen);
 }
 
 static int efx_mcdi_poll(struct efx_nic *efx)
@@ -125,7 +110,6 @@ static int efx_mcdi_poll(struct efx_nic *efx)
 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
 	unsigned long time, finish;
 	unsigned int respseq, respcmd, error;
-	unsigned int pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
 	unsigned int rc, spins;
 	efx_dword_t reg;
 
@@ -152,19 +136,14 @@ static int efx_mcdi_poll(struct efx_nic *efx)
 		time = jiffies;
 
 		rmb();
-		efx_readd(efx, &reg, pdu);
-
-		/* All 1's indicates that shared memory is in reset (and is
-		 * not a valid header). Wait for it to come out reset before
-		 * completing the command */
-		if (EFX_DWORD_FIELD(reg, EFX_DWORD_0) != 0xffffffff &&
-		    EFX_DWORD_FIELD(reg, MCDI_HEADER_RESPONSE))
+		if (efx->type->mcdi_poll_response(efx))
 			break;
 
 		if (time_after(time, finish))
 			return -ETIMEDOUT;
 	}
 
+	efx->type->mcdi_read_response(efx, &reg, 0, 4);
 	mcdi->resplen = EFX_DWORD_FIELD(reg, MCDI_HEADER_DATALEN);
 	respseq = EFX_DWORD_FIELD(reg, MCDI_HEADER_SEQ);
 	respcmd = EFX_DWORD_FIELD(reg, MCDI_HEADER_CODE);
@@ -179,7 +158,7 @@ static int efx_mcdi_poll(struct efx_nic *efx)
 			  respseq, mcdi->seqno);
 		rc = EIO;
 	} else if (error) {
-		efx_readd(efx, &reg, pdu + 4);
+		efx->type->mcdi_read_response(efx, &reg, 4, 4);
 		switch (EFX_DWORD_FIELD(reg, EFX_DWORD_0)) {
 #define TRANSLATE_ERROR(name)					\
 		case MC_CMD_ERR_ ## name:			\
@@ -215,17 +194,13 @@ static int efx_mcdi_poll(struct efx_nic *efx)
  */
 int efx_mcdi_poll_reboot(struct efx_nic *efx)
 {
-	unsigned int addr = FR_CZ_MC_TREG_SMEM + MCDI_STATUS(efx);
-	efx_dword_t reg;
-	uint32_t value;
-
-	if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
-		return false;
+	int rc;
 
-	efx_readd(efx, &reg, addr);
-	value = EFX_DWORD_FIELD(reg, EFX_DWORD_0);
+	if (!efx->mcdi)
+		return 0;
 
-	if (value == 0)
+	rc = efx->type->mcdi_poll_reboot(efx);
+	if (!rc)
 		return 0;
 
 	/* MAC statistics have been cleared on the NIC; clear our copy
@@ -233,13 +208,7 @@ int efx_mcdi_poll_reboot(struct efx_nic *efx)
 	 */
 	memset(&efx->mac_stats, 0, sizeof(efx->mac_stats));
 
-	EFX_ZERO_DWORD(reg);
-	efx_writed(efx, &reg, addr);
-
-	if (value == MC_STATUS_DWORD_ASSERT)
-		return -EINTR;
-	else
-		return -EIO;
+	return rc;
 }
 
 static void efx_mcdi_acquire(struct efx_mcdi_iface *mcdi)
@@ -345,8 +314,6 @@ void efx_mcdi_rpc_start(struct efx_nic *efx, unsigned cmd,
 {
 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
 
-	BUG_ON(efx_nic_rev(efx) < EFX_REV_SIENA_A0);
-
 	efx_mcdi_acquire(mcdi);
 
 	/* Serialise with efx_mcdi_ev_cpl() and efx_mcdi_ev_death() */
@@ -364,8 +331,6 @@ int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
 	struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
 	int rc;
 
-	BUG_ON(efx_nic_rev(efx) < EFX_REV_SIENA_A0);
-
 	if (mcdi->mode == MCDI_MODE_POLL)
 		rc = efx_mcdi_poll(efx);
 	else
@@ -426,7 +391,7 @@ void efx_mcdi_mode_poll(struct efx_nic *efx)
 {
 	struct efx_mcdi_iface *mcdi;
 
-	if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
+	if (!efx->mcdi)
 		return;
 
 	mcdi = efx_mcdi(efx);
@@ -450,7 +415,7 @@ void efx_mcdi_mode_event(struct efx_nic *efx)
 {
 	struct efx_mcdi_iface *mcdi;
 
-	if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
+	if (!efx->mcdi)
 		return;
 
 	mcdi = efx_mcdi(efx);

drivers/net/ethernet/sfc/mcdi.h

@@ -65,7 +65,28 @@ struct efx_mcdi_mon {
 	unsigned int n_attrs;
 };
 
+/**
+ * struct efx_mcdi_data - extra state for NICs that implement MCDI
+ * @iface: Interface/protocol state
+ * @hwmon: Hardware monitor state
+ */
+struct efx_mcdi_data {
+	struct efx_mcdi_iface iface;
+#ifdef CONFIG_SFC_MCDI_MON
+	struct efx_mcdi_mon hwmon;
+#endif
+};
+
+#ifdef CONFIG_SFC_MCDI_MON
+static inline struct efx_mcdi_mon *efx_mcdi_mon(struct efx_nic *efx)
+{
+	EFX_BUG_ON_PARANOID(!efx->mcdi);
+	return &efx->mcdi->hwmon;
+}
+#endif
+
 extern int efx_mcdi_init(struct efx_nic *efx);
+extern void efx_mcdi_fini(struct efx_nic *efx);
 
 extern int efx_mcdi_rpc(struct efx_nic *efx, unsigned cmd,
 			const efx_dword_t *inbuf, size_t inlen,

drivers/net/ethernet/sfc/net_driver.h

@@ -718,6 +718,7 @@ struct vfdi_status;
  * @selftest_work: Work item for asynchronous self-test
  * @mtd_list: List of MTDs attached to the NIC
  * @nic_data: Hardware dependent state
+ * @mcdi: Management-Controller-to-Driver Interface state
  * @mac_lock: MAC access lock. Protects @port_enabled, @phy_mode,
  *	efx_monitor() and efx_reconfigure_port()
  * @port_enabled: Port enabled indicator.
@@ -847,6 +848,7 @@ struct efx_nic {
 #endif
 
 	void *nic_data;
+	struct efx_mcdi_data *mcdi;
 
 	struct mutex mac_lock;
 	struct work_struct mac_work;
@@ -956,6 +958,17 @@ static inline unsigned int efx_port_num(struct efx_nic *efx)
  * @test_chip: Test registers.  Should use efx_nic_test_registers(), and is
  *	expected to reset the NIC.
  * @test_nvram: Test validity of NVRAM contents
+ * @mcdi_request: Send an MCDI request with the given header and SDU.
+ *	The SDU length may be any value from 0 up to the protocol-
+ *	defined maximum, but its buffer will be padded to a multiple
+ *	of 4 bytes.
+ * @mcdi_poll_response: Test whether an MCDI response is available.
+ * @mcdi_read_response: Read the MCDI response PDU.  The offset will
+ *	be a multiple of 4.  The length may not be, but the buffer
+ *	will be padded so it is safe to round up.
+ * @mcdi_poll_reboot: Test whether the MCDI has rebooted.  If so,
+ *	return an appropriate error code for aborting any current
+ *	request; otherwise return 0.
  * @revision: Hardware architecture revision
  * @mem_map_size: Memory BAR mapped size
  * @txd_ptr_tbl_base: TX descriptor ring base address
@@ -1004,6 +1017,13 @@ struct efx_nic_type {
 	void (*resume_wol)(struct efx_nic *efx);
 	int (*test_chip)(struct efx_nic *efx, struct efx_self_tests *tests);
 	int (*test_nvram)(struct efx_nic *efx);
+	void (*mcdi_request)(struct efx_nic *efx,
+			     const efx_dword_t *hdr, size_t hdr_len,
+			     const efx_dword_t *sdu, size_t sdu_len);
+	bool (*mcdi_poll_response)(struct efx_nic *efx);
+	void (*mcdi_read_response)(struct efx_nic *efx, efx_dword_t *pdu,
+				   size_t pdu_offset, size_t pdu_len);
+	int (*mcdi_poll_reboot)(struct efx_nic *efx);
 
 	int revision;
 	unsigned int mem_map_size;

drivers/net/ethernet/sfc/nic.h

@@ -140,28 +140,12 @@ static inline struct falcon_board *falcon_board(struct efx_nic *efx)
 
 /**
  * struct siena_nic_data - Siena NIC state
- * @mcdi: Management-Controller-to-Driver Interface
  * @wol_filter_id: Wake-on-LAN packet filter id
- * @hwmon: Hardware monitor state
  */
 struct siena_nic_data {
-	struct efx_mcdi_iface mcdi;
 	int wol_filter_id;
-#ifdef CONFIG_SFC_MCDI_MON
-	struct efx_mcdi_mon hwmon;
-#endif
 };
 
-#ifdef CONFIG_SFC_MCDI_MON
-static inline struct efx_mcdi_mon *efx_mcdi_mon(struct efx_nic *efx)
-{
-	struct siena_nic_data *nic_data;
-	EFX_BUG_ON_PARANOID(efx_nic_rev(efx) < EFX_REV_SIENA_A0);
-	nic_data = efx->nic_data;
-	return &nic_data->hwmon;
-}
-#endif
-
 /*
  * On the SFC9000 family each port is associated with 1 PCI physical
  * function (PF) handled by sfc and a configurable number of virtual

drivers/net/ethernet/sfc/siena.c

@@ -274,6 +274,7 @@ static int siena_probe_nic(struct efx_nic *efx)
 fail3:
 	efx_mcdi_drv_attach(efx, false, NULL);
 fail2:
+	efx_mcdi_fini(efx);
 fail1:
 	kfree(efx->nic_data);
 	return rc;
@@ -367,6 +368,8 @@ static void siena_remove_nic(struct efx_nic *efx)
 	/* Tear down the private nic state */
 	kfree(efx->nic_data);
 	efx->nic_data = NULL;
+
+	efx_mcdi_fini(efx);
 }
 
 static int siena_try_update_nic_stats(struct efx_nic *efx)
@@ -574,6 +577,89 @@ static void siena_init_wol(struct efx_nic *efx)
 	}
 }
 
+/**************************************************************************
+ *
+ * MCDI
+ *
+ **************************************************************************
+ */
+
+#define MCDI_PDU(efx)							\
+	(efx_port_num(efx) ? MC_SMEM_P1_PDU_OFST : MC_SMEM_P0_PDU_OFST)
+#define MCDI_DOORBELL(efx)						\
+	(efx_port_num(efx) ? MC_SMEM_P1_DOORBELL_OFST : MC_SMEM_P0_DOORBELL_OFST)
+#define MCDI_STATUS(efx)						\
+	(efx_port_num(efx) ? MC_SMEM_P1_STATUS_OFST : MC_SMEM_P0_STATUS_OFST)
+
+static void siena_mcdi_request(struct efx_nic *efx,
+			       const efx_dword_t *hdr, size_t hdr_len,
+			       const efx_dword_t *sdu, size_t sdu_len)
+{
+	unsigned pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
+	unsigned doorbell = FR_CZ_MC_TREG_SMEM + MCDI_DOORBELL(efx);
+	unsigned int i;
+	unsigned int inlen_dw = DIV_ROUND_UP(sdu_len, 4);
+
+	EFX_BUG_ON_PARANOID(hdr_len != 4);
+
+	efx_writed(efx, hdr, pdu);
+
+	for (i = 0; i < inlen_dw; i++)
+		efx_writed(efx, &sdu[i], pdu + hdr_len + 4 * i);
+
+	/* Ensure the request is written out before the doorbell */
+	wmb();
+
+	/* ring the doorbell with a distinctive value */
+	_efx_writed(efx, (__force __le32) 0x45789abc, doorbell);
+}
+
+static bool siena_mcdi_poll_response(struct efx_nic *efx)
+{
+	unsigned int pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
+	efx_dword_t hdr;
+
+	efx_readd(efx, &hdr, pdu);
+
+	/* All 1's indicates that shared memory is in reset (and is
+	 * not a valid hdr). Wait for it to come out reset before
+	 * completing the command
+	 */
+	return EFX_DWORD_FIELD(hdr, EFX_DWORD_0) != 0xffffffff &&
+		EFX_DWORD_FIELD(hdr, MCDI_HEADER_RESPONSE);
+}
+
+static void siena_mcdi_read_response(struct efx_nic *efx, efx_dword_t *outbuf,
+				     size_t offset, size_t outlen)
+{
+	unsigned int pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
+	unsigned int outlen_dw = DIV_ROUND_UP(outlen, 4);
+	int i;
+
+	for (i = 0; i < outlen_dw; i++)
+		efx_readd(efx, &outbuf[i], pdu + offset + 4 * i);
+}
+
+static int siena_mcdi_poll_reboot(struct efx_nic *efx)
+{
+	unsigned int addr = FR_CZ_MC_TREG_SMEM + MCDI_STATUS(efx);
+	efx_dword_t reg;
+	u32 value;
+
+	efx_readd(efx, &reg, addr);
+	value = EFX_DWORD_FIELD(reg, EFX_DWORD_0);
+
+	if (value == 0)
+		return 0;
+
+	EFX_ZERO_DWORD(reg);
+	efx_writed(efx, &reg, addr);
+
+	if (value == MC_STATUS_DWORD_ASSERT)
+		return -EINTR;
+	else
+		return -EIO;
+}
 
 /**************************************************************************
  *
@@ -613,6 +699,10 @@ const struct efx_nic_type siena_a0_nic_type = {
 	.resume_wol = siena_init_wol,
 	.test_chip = siena_test_chip,
 	.test_nvram = efx_mcdi_nvram_test_all,
+	.mcdi_request = siena_mcdi_request,
+	.mcdi_poll_response = siena_mcdi_poll_response,
+	.mcdi_read_response = siena_mcdi_read_response,
+	.mcdi_poll_reboot = siena_mcdi_poll_reboot,
 
 	.revision = EFX_REV_SIENA_A0,
 	.mem_map_size = (FR_CZ_MC_TREG_SMEM +