[PATCH net-next v3 3/7] net: phy: meson-gxl: add read and write helpers for banked registers

From: Jerome Brunet
Date: Mon Dec 18 2017 - 04:45:19 EST


Add read and write helpers to manipulate banked registers on this PHY
This helps clarify the settings applied to these registers and what the
driver actually does

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
---
drivers/net/phy/meson-gxl.c | 130 +++++++++++++++++++++++---------------------
1 file changed, 69 insertions(+), 61 deletions(-)

diff --git a/drivers/net/phy/meson-gxl.c b/drivers/net/phy/meson-gxl.c
index 61bcc17098d7..a52645566d0d 100644
--- a/drivers/net/phy/meson-gxl.c
+++ b/drivers/net/phy/meson-gxl.c
@@ -50,11 +50,13 @@
#define FR_PLL_DIV0 0x1c
#define FR_PLL_DIV1 0x1d

-static int meson_gxl_config_init(struct phy_device *phydev)
+static int meson_gxl_open_banks(struct phy_device *phydev)
{
int ret;

- /* Enable Analog and DSP register Bank access by */
+ /* Enable Analog and DSP register Bank access by
+ * toggling TSTCNTL_TEST_MODE bit in the TSTCNTL register
+ */
ret = phy_write(phydev, TSTCNTL, 0);
if (ret)
return ret;
@@ -64,55 +66,84 @@ static int meson_gxl_config_init(struct phy_device *phydev)
ret = phy_write(phydev, TSTCNTL, 0);
if (ret)
return ret;
- ret = phy_write(phydev, TSTCNTL, TSTCNTL_TEST_MODE);
- if (ret)
- return ret;
+ return phy_write(phydev, TSTCNTL, TSTCNTL_TEST_MODE);
+}

- /* Write CONFIG_A6*/
- ret = phy_write(phydev, TSTWRITE, 0x8e0d);
+static void meson_gxl_close_banks(struct phy_device *phydev)
+{
+ phy_write(phydev, TSTCNTL, 0);
+}
+
+static int meson_gxl_read_reg(struct phy_device *phydev,
+ unsigned int bank, unsigned int reg)
+{
+ int ret;
+
+ ret = meson_gxl_open_banks(phydev);
if (ret)
- return ret;
- ret = phy_write(phydev, TSTCNTL,
- TSTCNTL_WRITE
- | FIELD_PREP(TSTCNTL_REG_BANK_SEL, BANK_ANALOG_DSP)
- | TSTCNTL_TEST_MODE
- | FIELD_PREP(TSTCNTL_WRITE_ADDRESS, A6_CONFIG_REG));
+ goto out;
+
+ ret = phy_write(phydev, TSTCNTL, TSTCNTL_READ |
+ FIELD_PREP(TSTCNTL_REG_BANK_SEL, bank) |
+ TSTCNTL_TEST_MODE |
+ FIELD_PREP(TSTCNTL_READ_ADDRESS, reg));
if (ret)
- return ret;
+ goto out;

- /* Enable fractional PLL */
- ret = phy_write(phydev, TSTWRITE, 0x0005);
+ ret = phy_read(phydev, TSTREAD1);
+out:
+ /* Close the bank access on our way out */
+ meson_gxl_close_banks(phydev);
+ return ret;
+}
+
+static int meson_gxl_write_reg(struct phy_device *phydev,
+ unsigned int bank, unsigned int reg,
+ uint16_t value)
+{
+ int ret;
+
+ ret = meson_gxl_open_banks(phydev);
if (ret)
- return ret;
- ret = phy_write(phydev, TSTCNTL,
- TSTCNTL_WRITE
- | FIELD_PREP(TSTCNTL_REG_BANK_SEL, BANK_BIST)
- | TSTCNTL_TEST_MODE
- | FIELD_PREP(TSTCNTL_WRITE_ADDRESS, FR_PLL_CONTROL));
+ goto out;
+
+ ret = phy_write(phydev, TSTWRITE, value);
if (ret)
- return ret;
+ goto out;

- /* Program fraction FR_PLL_DIV1 */
- ret = phy_write(phydev, TSTWRITE, 0x029a);
+ ret = phy_write(phydev, TSTCNTL, TSTCNTL_WRITE |
+ FIELD_PREP(TSTCNTL_REG_BANK_SEL, bank) |
+ TSTCNTL_TEST_MODE |
+ FIELD_PREP(TSTCNTL_WRITE_ADDRESS, reg));
+
+out:
+ /* Close the bank access on our way out */
+ meson_gxl_close_banks(phydev);
+ return ret;
+}
+
+static int meson_gxl_config_init(struct phy_device *phydev)
+{
+ int ret;
+
+ /* Write CONFIG_A6*/
+ ret = meson_gxl_write_reg(phydev, BANK_ANALOG_DSP, A6_CONFIG_REG,
+ 0x8e0d);
if (ret)
return ret;
- ret = phy_write(phydev, TSTCNTL,
- TSTCNTL_WRITE
- | FIELD_PREP(TSTCNTL_REG_BANK_SEL, BANK_BIST)
- | TSTCNTL_TEST_MODE
- | FIELD_PREP(TSTCNTL_WRITE_ADDRESS, FR_PLL_DIV1));
+
+ /* Enable fractional PLL */
+ ret = meson_gxl_write_reg(phydev, BANK_BIST, FR_PLL_CONTROL, 0x5);
if (ret)
return ret;

/* Program fraction FR_PLL_DIV1 */
- ret = phy_write(phydev, TSTWRITE, 0xaaaa);
+ ret = meson_gxl_write_reg(phydev, BANK_BIST, FR_PLL_DIV1, 0x029a);
if (ret)
return ret;
- ret = phy_write(phydev, TSTCNTL,
- TSTCNTL_WRITE
- | FIELD_PREP(TSTCNTL_REG_BANK_SEL, BANK_BIST)
- | TSTCNTL_TEST_MODE
- | FIELD_PREP(TSTCNTL_WRITE_ADDRESS, FR_PLL_DIV0));
+
+ /* Program fraction FR_PLL_DIV1 */
+ ret = meson_gxl_write_reg(phydev, BANK_BIST, FR_PLL_DIV0, 0xaaaa);
if (ret)
return ret;

@@ -146,31 +177,8 @@ static int meson_gxl_read_status(struct phy_device *phydev)
else if (!ret)
goto read_status_continue;

- /* Need to access WOL bank, make sure the access is open */
- ret = phy_write(phydev, TSTCNTL, 0);
- if (ret)
- return ret;
- ret = phy_write(phydev, TSTCNTL, TSTCNTL_TEST_MODE);
- if (ret)
- return ret;
- ret = phy_write(phydev, TSTCNTL, 0);
- if (ret)
- return ret;
- ret = phy_write(phydev, TSTCNTL, TSTCNTL_TEST_MODE);
- if (ret)
- return ret;
-
- /* Request LPI_STATUS WOL register */
- ret = phy_write(phydev, TSTCNTL,
- TSTCNTL_READ
- | FIELD_PREP(TSTCNTL_REG_BANK_SEL, BANK_WOL)
- | TSTCNTL_TEST_MODE
- | FIELD_PREP(TSTCNTL_READ_ADDRESS, LPI_STATUS));
- if (ret)
- return ret;
-
- /* Read LPI_STATUS value */
- wol = phy_read(phydev, TSTREAD1);
+ /* Aneg is done, let's check everything is fine */
+ wol = meson_gxl_read_reg(phydev, BANK_WOL, LPI_STATUS);
if (wol < 0)
return wol;

--
2.14.3