[PATCH 3/3] hisi_sas: add v2 hw support for different refclk

[John Garry]

Some hip06 D03 and hip07 D05 boards have different
reference clock frequencies for the SAS controller.

Register PHY_CTRL needs to be programmed differently
according to this frequency, so add support for this.

The default register setting in PHY_CTRL is for 50MHz,
so only update this register when the refclk frequency
is 66MHz.

The register cannot be set according to hip06 or hip07
as some variants of hip06 D03 board are 50MHz and some
are 66MHz (early editions). All hip07 D05 are 50MHz.

For ACPI we expect the _RST handler to set the correct
value for PHY_CTRL (we take an alternate approach for
DT and ACPI as ACPI does not support fixed-clock device
type).

Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
Signed-off-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
---
 drivers/scsi/hisi_sas/hisi_sas.h       | 2 ++
 drivers/scsi/hisi_sas/hisi_sas_main.c  | 7 +++++++
 drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 4 +++-
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 72c9852..64046c5 100644
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -13,6 +13,7 @@
 #define _HISI_SAS_H_
 
 #include <linux/acpi.h>
+#include <linux/clk.h>
 #include <linux/dmapool.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
@@ -183,6 +184,7 @@ struct hisi_hba {
 	u32 ctrl_reset_reg;
 	u32 ctrl_reset_sts_reg;
 	u32 ctrl_clock_ena_reg;
+	u32 refclk_frequency_mhz;
 	u8 sas_addr[SAS_ADDR_SIZE];
 
 	int n_phy;
diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 2f872f7..0bc3165 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1396,6 +1396,7 @@ static struct Scsi_Host *hisi_sas_shost_alloc(struct platform_device *pdev,
 	struct hisi_hba *hisi_hba;
 	struct device *dev = &pdev->dev;
 	struct device_node *np = pdev->dev.of_node;
+	struct clk *refclk;
 
 	shost = scsi_host_alloc(&hisi_sas_sht, sizeof(*hisi_hba));
 	if (!shost)
@@ -1432,6 +1433,12 @@ static struct Scsi_Host *hisi_sas_shost_alloc(struct platform_device *pdev,
 			goto err_out;
 	}
 
+	refclk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(refclk))
+		dev_info(dev, "no ref clk property\n");
+	else
+		hisi_hba->refclk_frequency_mhz = clk_get_rate(refclk) / 1000000;
+
 	if (device_property_read_u32(dev, "phy-count", &hisi_hba->n_phy))
 		goto err_out;
 
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
index c1e3aa7..7014d99 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
@@ -837,7 +837,9 @@ static void init_reg_v2_hw(struct hisi_hba *hisi_hba)
 		hisi_sas_phy_write32(hisi_hba, i, SL_RX_BCAST_CHK_MSK, 0x0);
 		hisi_sas_phy_write32(hisi_hba, i, CHL_INT_COAL_EN, 0x0);
 		hisi_sas_phy_write32(hisi_hba, i, PHYCTRL_OOB_RESTART_MSK, 0x0);
-		hisi_sas_phy_write32(hisi_hba, i, PHY_CTRL, 0x199B694);
+		if (hisi_hba->refclk_frequency_mhz == 66)
+			hisi_sas_phy_write32(hisi_hba, i, PHY_CTRL, 0x199B694);
+		/* else, do nothing -> leave it how you found it */
 	}
 
 	for (i = 0; i < hisi_hba->queue_count; i++) {
-- 
1.9.1