diff mbox series

[net-next,v4,04/12] net: ethernet: oa_tc6: implement software reset

Message ID 20240418125648.372526-5-Parthiban.Veerasooran@microchip.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series Add support for OPEN Alliance 10BASE-T1x MACPHY Serial Interface | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/apply fail Patch does not apply to net-next-1

Commit Message

Parthiban Veerasooran April 18, 2024, 12:56 p.m. UTC 
Reset complete bit is set when the MAC-PHY reset completes and ready for
configuration. Additionally reset complete bit in the STS0 register has
to be written by one upon reset complete to clear the interrupt.

Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@microchip.com>
---
 drivers/net/ethernet/oa_tc6.c | 53 +++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

Comments

Andrew Lunn April 23, 2024, 11:26 p.m. UTC | #1 
> +static int oa_tc6_read_status0(struct oa_tc6 *tc6)
> +{
> +	u32 regval;
> +	int ret;
> +
> +	ret = oa_tc6_read_register(tc6, OA_TC6_REG_STATUS0, &regval);
> +	if (ret)
> +		return 0;

If there is an error, your throw the error code away?

It is a bit messy, since you are using this inside
readx_poll_timeout(). I would probably do a netdev_warn() or similar,
since it should not happen, and then return 0? I _think_ this is
probably the first bus transaction we do, so if it fails, knowing the
error code will help figuring out what is wrong with the SPI bus
configuration.

	Andrew
Parthiban Veerasooran April 26, 2024, 6:38 a.m. UTC | #2 
Hi Andrew,

On 24/04/24 4:56 am, Andrew Lunn wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
>> +static int oa_tc6_read_status0(struct oa_tc6 *tc6)
>> +{
>> +     u32 regval;
>> +     int ret;
>> +
>> +     ret = oa_tc6_read_register(tc6, OA_TC6_REG_STATUS0, &regval);
>> +     if (ret)
>> +             return 0;
> 
> If there is an error, your throw the error code away?
> 
> It is a bit messy, since you are using this inside
> readx_poll_timeout(). I would probably do a netdev_warn() or similar,
> since it should not happen, and then return 0? I _think_ this is
> probably the first bus transaction we do, so if it fails, knowing the
> error code will help figuring out what is wrong with the SPI bus
> configuration.
OK, I will add the below print before "return 0;" in the next version.

dev_err(&tc6->spi->dev, "STATUS0 register read failed: %d\n", ret);

Best regards,
Parthiban V
> 
>          Andrew
>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c
index f563329912e2..4b0f63c02c35 100644
--- a/drivers/net/ethernet/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6.c
@@ -6,8 +6,18 @@ 
  */
 
 #include <linux/bitfield.h>
+#include <linux/iopoll.h>
 #include <linux/oa_tc6.h>
 
+/* OPEN Alliance TC6 registers */
+/* Reset Control and Status Register */
+#define OA_TC6_REG_RESET			0x0003
+#define RESET_SWRESET				BIT(0)	/* Software Reset */
+
+/* Status Register #0 */
+#define OA_TC6_REG_STATUS0			0x0008
+#define STATUS0_RESETC				BIT(6)	/* Reset Complete */
+
 /* Control command header */
 #define OA_TC6_CTRL_HEADER_DATA_NOT_CTRL	BIT(31)
 #define OA_TC6_CTRL_HEADER_WRITE_NOT_READ	BIT(29)
@@ -24,6 +34,8 @@ 
 						(OA_TC6_CTRL_MAX_REGISTERS *\
 						OA_TC6_CTRL_REG_VALUE_SIZE) +\
 						OA_TC6_CTRL_IGNORED_SIZE)
+#define STATUS0_RESETC_POLL_DELAY		1000
+#define STATUS0_RESETC_POLL_TIMEOUT		1000000
 
 /* Internal structure for MAC-PHY drivers */
 struct oa_tc6 {
@@ -279,6 +291,39 @@  int oa_tc6_write_register(struct oa_tc6 *tc6, u32 address, u32 value)
 }
 EXPORT_SYMBOL_GPL(oa_tc6_write_register);
 
+static int oa_tc6_read_status0(struct oa_tc6 *tc6)
+{
+	u32 regval;
+	int ret;
+
+	ret = oa_tc6_read_register(tc6, OA_TC6_REG_STATUS0, &regval);
+	if (ret)
+		return 0;
+
+	return regval;
+}
+
+static int oa_tc6_sw_reset_macphy(struct oa_tc6 *tc6)
+{
+	u32 regval = RESET_SWRESET;
+	int ret;
+
+	ret = oa_tc6_write_register(tc6, OA_TC6_REG_RESET, regval);
+	if (ret)
+		return ret;
+
+	/* Poll for soft reset complete for every 1ms until 1s timeout */
+	ret = readx_poll_timeout(oa_tc6_read_status0, tc6, regval,
+				 regval & STATUS0_RESETC,
+				 STATUS0_RESETC_POLL_DELAY,
+				 STATUS0_RESETC_POLL_TIMEOUT);
+	if (ret)
+		return -ENODEV;
+
+	/* Clear the reset complete status */
+	return oa_tc6_write_register(tc6, OA_TC6_REG_STATUS0, regval);
+}
+
 /**
  * oa_tc6_init - allocates and initializes oa_tc6 structure.
  * @spi: device with which data will be exchanged.
@@ -289,6 +334,7 @@  EXPORT_SYMBOL_GPL(oa_tc6_write_register);
 struct oa_tc6 *oa_tc6_init(struct spi_device *spi)
 {
 	struct oa_tc6 *tc6;
+	int ret;
 
 	tc6 = devm_kzalloc(&spi->dev, sizeof(*tc6), GFP_KERNEL);
 	if (!tc6)
@@ -311,6 +357,13 @@  struct oa_tc6 *oa_tc6_init(struct spi_device *spi)
 	if (!tc6->spi_ctrl_rx_buf)
 		return NULL;
 
+	ret = oa_tc6_sw_reset_macphy(tc6);
+	if (ret) {
+		dev_err(&tc6->spi->dev,
+			"MAC-PHY software reset failed: %d\n", ret);
+		return NULL;
+	}
+
 	return tc6;
 }
 EXPORT_SYMBOL_GPL(oa_tc6_init);