scsi: pm80xx: Do not request 12G sas speeds

Occasionally, 6G capable drives fail to train at 6G on links that look good
from a signal-integrity perspective. PMC suggests configuring the port to
not even expect 12G.

Link: https://lore.kernel.org/r/20191114100910.6153-11-deepak.ukey@microchip.comAcked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: peter chang <dpf@google.com>
Signed-off-by: Deepak Ukey <deepak.ukey@microchip.com>
Signed-off-by: Viswas G <Viswas.G@microchip.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/pm8001/pm8001_init.c

@@ -41,11 +41,20 @@
 #include <linux/slab.h>
 #include "pm8001_sas.h"
 #include "pm8001_chips.h"
+#include "pm80xx_hwi.h"
 
 static ulong logging_level = PM8001_FAIL_LOGGING | PM8001_IOERR_LOGGING;
 module_param(logging_level, ulong, 0644);
 MODULE_PARM_DESC(logging_level, " bits for enabling logging info.");
 
+static ulong link_rate = LINKRATE_15 | LINKRATE_30 | LINKRATE_60 | LINKRATE_120;
+module_param(link_rate, ulong, 0644);
+MODULE_PARM_DESC(link_rate, "Enable link rate.\n"
+		" 1: Link rate 1.5G\n"
+		" 2: Link rate 3.0G\n"
+		" 4: Link rate 6.0G\n"
+		" 8: Link rate 12.0G\n");
+
 static struct scsi_transport_template *pm8001_stt;
 
 /**
@@ -471,6 +480,14 @@ static struct pm8001_hba_info *pm8001_pci_alloc(struct pci_dev *pdev,
 	pm8001_ha->shost = shost;
 	pm8001_ha->id = pm8001_id++;
 	pm8001_ha->logging_level = logging_level;
+	if (link_rate >= 1 && link_rate <= 15)
+		pm8001_ha->link_rate = (link_rate << 8);
+	else {
+		pm8001_ha->link_rate = LINKRATE_15 | LINKRATE_30 |
+			LINKRATE_60 | LINKRATE_120;
+		PM8001_FAIL_DBG(pm8001_ha, pm8001_printk(
+			"Setting link rate to default value\n"));
+	}
 	sprintf(pm8001_ha->name, "%s%d", DRV_NAME, pm8001_ha->id);
 	/* IOMB size is 128 for 8088/89 controllers */
 	if (pm8001_ha->chip_id != chip_8001)

drivers/scsi/pm8001/pm8001_sas.h

@@ -546,6 +546,7 @@ struct pm8001_hba_info {
 	struct tasklet_struct	tasklet[PM8001_MAX_MSIX_VEC];
 #endif
 	u32			logging_level;
+	u32			link_rate;
 	u32			fw_status;
 	u32			smp_exp_mode;
 	bool			controller_fatal_error;

drivers/scsi/pm8001/pm80xx_hwi.c

@@ -37,6 +37,7 @@
  * POSSIBILITY OF SUCH DAMAGES.
  *
  */
+ #include <linux/version.h>
  #include <linux/slab.h>
  #include "pm8001_sas.h"
  #include "pm80xx_hwi.h"
@@ -4565,23 +4566,9 @@ pm80xx_chip_phy_start_req(struct pm8001_hba_info *pm8001_ha, u8 phy_id)
 
 	PM8001_INIT_DBG(pm8001_ha,
 		pm8001_printk("PHY START REQ for phy_id %d\n", phy_id));
-	/*
-	 ** [0:7]	PHY Identifier
-	 ** [8:11]	link rate 1.5G, 3G, 6G
-	 ** [12:13] link mode 01b SAS mode; 10b SATA mode; 11b Auto mode
-	 ** [14]	0b disable spin up hold; 1b enable spin up hold
-	 ** [15] ob no change in current PHY analig setup 1b enable using SPAST
-	 */
-	if (!IS_SPCV_12G(pm8001_ha->pdev))
-		payload.ase_sh_lm_slr_phyid = cpu_to_le32(SPINHOLD_DISABLE |
-				LINKMODE_AUTO | LINKRATE_15 |
-				LINKRATE_30 | LINKRATE_60 | phy_id);
-	else
-		payload.ase_sh_lm_slr_phyid = cpu_to_le32(SPINHOLD_DISABLE |
-				LINKMODE_AUTO | LINKRATE_15 |
-				LINKRATE_30 | LINKRATE_60 | LINKRATE_120 |
-				phy_id);
 
+	payload.ase_sh_lm_slr_phyid = cpu_to_le32(SPINHOLD_DISABLE |
+			LINKMODE_AUTO | pm8001_ha->link_rate | phy_id);
 	/* SSC Disable and SAS Analog ST configuration */
 	/**
 	payload.ase_sh_lm_slr_phyid =
@@ -4594,7 +4581,7 @@ pm80xx_chip_phy_start_req(struct pm8001_hba_info *pm8001_ha, u8 phy_id)
 	payload.sas_identify.dev_type = SAS_END_DEVICE;
 	payload.sas_identify.initiator_bits = SAS_PROTOCOL_ALL;
 	memcpy(payload.sas_identify.sas_addr,
-	  &pm8001_ha->phy[phy_id].dev_sas_addr, SAS_ADDR_SIZE);
+	  &pm8001_ha->sas_addr, SAS_ADDR_SIZE);
 	payload.sas_identify.phy_id = phy_id;
 	ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opcode, &payload,
 			sizeof(payload), 0);