[PATCH v2 2/2 net-next] net: stmmac: dwmac-qcom-ethqos: Adjust rgmii loopback_en per platform

From: Bhupesh Sharma
Date: Wed Mar 02 2022 - 05:40:15 EST


From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Not all platforms should have RGMII_CONFIG_LOOPBACK_EN and the result it
about 50% packet loss on incoming messages. So make it possile to
configure this per compatible and enable it for QCS404.

Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---
.../stmicro/stmmac/dwmac-qcom-ethqos.c | 22 +++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index 8cdba9d521ec..0cc28c79cc61 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -78,6 +78,7 @@ struct ethqos_emac_por {
struct ethqos_emac_driver_data {
const struct ethqos_emac_por *por;
unsigned int num_por;
+ bool rgmii_config_looback_en;
};

struct qcom_ethqos {
@@ -90,6 +91,7 @@ struct qcom_ethqos {

const struct ethqos_emac_por *por;
unsigned int num_por;
+ bool rgmii_config_looback_en;
};

static int rgmii_readl(struct qcom_ethqos *ethqos, unsigned int offset)
@@ -181,6 +183,7 @@ static const struct ethqos_emac_por emac_v2_3_0_por[] = {
static const struct ethqos_emac_driver_data emac_v2_3_0_data = {
.por = emac_v2_3_0_por,
.num_por = ARRAY_SIZE(emac_v2_3_0_por),
+ .rgmii_config_looback_en = true,
};

static const struct ethqos_emac_por emac_v2_1_0_por[] = {
@@ -195,6 +198,7 @@ static const struct ethqos_emac_por emac_v2_1_0_por[] = {
static const struct ethqos_emac_driver_data emac_v2_1_0_data = {
.por = emac_v2_1_0_por,
.num_por = ARRAY_SIZE(emac_v2_1_0_por),
+ .rgmii_config_looback_en = false,
};

static int ethqos_dll_configure(struct qcom_ethqos *ethqos)
@@ -311,8 +315,12 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
rgmii_updatel(ethqos, SDCC_DDR_CONFIG_PRG_DLY_EN,
SDCC_DDR_CONFIG_PRG_DLY_EN,
SDCC_HC_REG_DDR_CONFIG);
- rgmii_updatel(ethqos, RGMII_CONFIG_LOOPBACK_EN,
- RGMII_CONFIG_LOOPBACK_EN, RGMII_IO_MACRO_CONFIG);
+ if (ethqos->rgmii_config_looback_en)
+ rgmii_updatel(ethqos, RGMII_CONFIG_LOOPBACK_EN,
+ RGMII_CONFIG_LOOPBACK_EN, RGMII_IO_MACRO_CONFIG);
+ else
+ rgmii_updatel(ethqos, RGMII_CONFIG_LOOPBACK_EN,
+ 0, RGMII_IO_MACRO_CONFIG);
break;

case SPEED_100:
@@ -345,8 +353,13 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
rgmii_updatel(ethqos, SDCC_DDR_CONFIG_EXT_PRG_RCLK_DLY_EN,
SDCC_DDR_CONFIG_EXT_PRG_RCLK_DLY_EN,
SDCC_HC_REG_DDR_CONFIG);
- rgmii_updatel(ethqos, RGMII_CONFIG_LOOPBACK_EN,
- RGMII_CONFIG_LOOPBACK_EN, RGMII_IO_MACRO_CONFIG);
+ if (ethqos->rgmii_config_looback_en)
+ rgmii_updatel(ethqos, RGMII_CONFIG_LOOPBACK_EN,
+ RGMII_CONFIG_LOOPBACK_EN, RGMII_IO_MACRO_CONFIG);
+ else
+ rgmii_updatel(ethqos, RGMII_CONFIG_LOOPBACK_EN,
+ 0, RGMII_IO_MACRO_CONFIG);
+
break;

case SPEED_10:
@@ -518,6 +531,7 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
data = of_device_get_match_data(&pdev->dev);
ethqos->por = data->por;
ethqos->num_por = data->num_por;
+ ethqos->rgmii_config_looback_en = data->rgmii_config_looback_en;

ethqos->rgmii_clk = devm_clk_get(&pdev->dev, "rgmii");
if (IS_ERR(ethqos->rgmii_clk)) {
--
2.35.1