Hi, On Mon 26 Oct 20, 16:38, Maxime Ripard wrote: > On Fri, Oct 23, 2020 at 07:45:34PM +0200, Paul Kocialkowski wrote: > > The Allwinner A31 D-PHY supports both Rx and Tx modes. While the latter > > is already supported and used for MIPI DSI this adds support for the > > former, to be used with MIPI CSI-2. > > > > This implementation is inspired by the Allwinner BSP implementation. > > Mentionning which BSP you took this from would be helpful Sure! It's from the Github repo linked from https://linux-sunxi.org/V3s. Would you like that I mention this URL explicitly or would it be enough to mention "Allwinner's V3s Linux SDK" as they seem to call it? > > Signed-off-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx> > > --- > > drivers/phy/allwinner/phy-sun6i-mipi-dphy.c | 164 +++++++++++++++++++- > > 1 file changed, 160 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/phy/allwinner/phy-sun6i-mipi-dphy.c b/drivers/phy/allwinner/phy-sun6i-mipi-dphy.c > > index 1fa761ba6cbb..8bcd4bb79f60 100644 > > --- a/drivers/phy/allwinner/phy-sun6i-mipi-dphy.c > > +++ b/drivers/phy/allwinner/phy-sun6i-mipi-dphy.c > > @@ -24,6 +24,14 @@ > > #define SUN6I_DPHY_TX_CTL_REG 0x04 > > #define SUN6I_DPHY_TX_CTL_HS_TX_CLK_CONT BIT(28) > > > > +#define SUN6I_DPHY_RX_CTL_REG 0x08 > > +#define SUN6I_DPHY_RX_CTL_EN_DBC BIT(31) > > +#define SUN6I_DPHY_RX_CTL_RX_CLK_FORCE BIT(24) > > +#define SUN6I_DPHY_RX_CTL_RX_D3_FORCE BIT(23) > > +#define SUN6I_DPHY_RX_CTL_RX_D2_FORCE BIT(22) > > +#define SUN6I_DPHY_RX_CTL_RX_D1_FORCE BIT(21) > > +#define SUN6I_DPHY_RX_CTL_RX_D0_FORCE BIT(20) > > + > > It's hard to tell from the diff, but it looks like you aligned the > BIT(..) with the register? That's correct, yes. > If so, you should follow the what the rest of this driver (ie, one more > indentation for register values). I'll fix it in the next revision! > > #define SUN6I_DPHY_TX_TIME0_REG 0x10 > > #define SUN6I_DPHY_TX_TIME0_HS_TRAIL(n) (((n) & 0xff) << 24) > > #define SUN6I_DPHY_TX_TIME0_HS_PREPARE(n) (((n) & 0xff) << 16) > > @@ -44,12 +52,29 @@ > > #define SUN6I_DPHY_TX_TIME4_HS_TX_ANA1(n) (((n) & 0xff) << 8) > > #define SUN6I_DPHY_TX_TIME4_HS_TX_ANA0(n) ((n) & 0xff) > > > > +#define SUN6I_DPHY_RX_TIME0_REG 0x30 > > +#define SUN6I_DPHY_RX_TIME0_HS_RX_SYNC(n) (((n) & 0xff) << 24) > > +#define SUN6I_DPHY_RX_TIME0_HS_RX_CLK_MISS(n) (((n) & 0xff) << 16) > > +#define SUN6I_DPHY_RX_TIME0_LP_RX(n) (((n) & 0xff) << 8) > > + > > +#define SUN6I_DPHY_RX_TIME1_REG 0x34 > > +#define SUN6I_DPHY_RX_TIME1_RX_DLY(n) (((n) & 0xfff) << 20) > > +#define SUN6I_DPHY_RX_TIME1_LP_RX_ULPS_WP(n) ((n) & 0xfffff) > > + > > +#define SUN6I_DPHY_RX_TIME2_REG 0x38 > > +#define SUN6I_DPHY_RX_TIME2_HS_RX_ANA1(n) (((n) & 0xff) << 8) > > +#define SUN6I_DPHY_RX_TIME2_HS_RX_ANA0(n) ((n) & 0xff) > > + > > +#define SUN6I_DPHY_RX_TIME3_REG 0x40 > > +#define SUN6I_DPHY_RX_TIME3_LPRST_DLY(n) (((n) & 0xffff) << 16) > > + > > #define SUN6I_DPHY_ANA0_REG 0x4c > > #define SUN6I_DPHY_ANA0_REG_PWS BIT(31) > > #define SUN6I_DPHY_ANA0_REG_DMPC BIT(28) > > #define SUN6I_DPHY_ANA0_REG_DMPD(n) (((n) & 0xf) << 24) > > #define SUN6I_DPHY_ANA0_REG_SLV(n) (((n) & 7) << 12) > > #define SUN6I_DPHY_ANA0_REG_DEN(n) (((n) & 0xf) << 8) > > +#define SUN6I_DPHY_ANA0_REG_SFB(n) (((n) & 3) << 2) > > > > #define SUN6I_DPHY_ANA1_REG 0x50 > > #define SUN6I_DPHY_ANA1_REG_VTTMODE BIT(31) > > @@ -92,6 +117,8 @@ struct sun6i_dphy { > > > > struct phy *phy; > > struct phy_configure_opts_mipi_dphy config; > > + > > + int submode; > > }; > > > > static int sun6i_dphy_init(struct phy *phy) > > @@ -105,6 +132,18 @@ static int sun6i_dphy_init(struct phy *phy) > > return 0; > > } > > > > +static int sun6i_dphy_set_mode(struct phy *phy, enum phy_mode mode, int submode) > > +{ > > + struct sun6i_dphy *dphy = phy_get_drvdata(phy); > > + > > + if (mode != PHY_MODE_MIPI_DPHY) > > + return -EINVAL; > > + > > + dphy->submode = submode; > > + > > + return 0; > > +} > > + > > static int sun6i_dphy_configure(struct phy *phy, union phy_configure_opts *opts) > > { > > struct sun6i_dphy *dphy = phy_get_drvdata(phy); > > @@ -119,9 +158,8 @@ static int sun6i_dphy_configure(struct phy *phy, union phy_configure_opts *opts) > > return 0; > > } > > > > -static int sun6i_dphy_power_on(struct phy *phy) > > +static int sun6i_dphy_tx_power_on(struct sun6i_dphy *dphy) > > { > > - struct sun6i_dphy *dphy = phy_get_drvdata(phy); > > u8 lanes_mask = GENMASK(dphy->config.lanes - 1, 0); > > > > regmap_write(dphy->regs, SUN6I_DPHY_TX_CTL_REG, > > @@ -211,12 +249,129 @@ static int sun6i_dphy_power_on(struct phy *phy) > > return 0; > > } > > > > +static int sun6i_dphy_rx_power_on(struct sun6i_dphy *dphy) > > +{ > > + /* Physical clock rate is actually half of symbol rate with DDR. */ > > + unsigned long mipi_symbol_rate = dphy->config.hs_clk_rate; > > + unsigned long dphy_clk_rate; > > + unsigned int rx_dly; > > + unsigned int lprst_dly; > > + u32 value; > > + > > + dphy_clk_rate = clk_get_rate(dphy->mod_clk); > > + if (!dphy_clk_rate) > > + return -1; > > Returning -1 is weird here? What do you think would be a more appropriate error code to return? It looks like some other drivers return -EINVAL when that happens (but many don't do the check). > > + > > + /* Hardcoded timing parameters from the Allwinner BSP. */ > > + regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME0_REG, > > + SUN6I_DPHY_RX_TIME0_HS_RX_SYNC(255) | > > + SUN6I_DPHY_RX_TIME0_HS_RX_CLK_MISS(255) | > > + SUN6I_DPHY_RX_TIME0_LP_RX(255)); > > + > > + /* > > + * Formula from the Allwinner BSP, with hardcoded coefficients > > + * (probably internal divider/multiplier). > > + */ > > + rx_dly = 8 * (unsigned int)(dphy_clk_rate / (mipi_symbol_rate / 8)); > > + > > + /* > > + * The Allwinner BSP has an alternative formula for LP_RX_ULPS_WP: > > + * lp_ulps_wp_cnt = lp_ulps_wp_ms * lp_clk / 1000 > > + * but does not use it and hardcodes 255 instead. > > + */ > > + regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME1_REG, > > + SUN6I_DPHY_RX_TIME1_RX_DLY(rx_dly) | > > + SUN6I_DPHY_RX_TIME1_LP_RX_ULPS_WP(255)); > > + > > + /* HS_RX_ANA0 value is hardcoded in the Allwinner BSP. */ > > + regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME2_REG, > > + SUN6I_DPHY_RX_TIME2_HS_RX_ANA0(4)); > > + > > + /* > > + * Formula from the Allwinner BSP, with hardcoded coefficients > > + * (probably internal divider/multiplier). > > + */ > > + lprst_dly = 4 * (unsigned int)(dphy_clk_rate / (mipi_symbol_rate / 2)); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME3_REG, > > + SUN6I_DPHY_RX_TIME3_LPRST_DLY(lprst_dly)); > > + > > + /* Analog parameters are hardcoded in the Allwinner BSP. */ > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA0_REG, > > + SUN6I_DPHY_ANA0_REG_PWS | > > + SUN6I_DPHY_ANA0_REG_SLV(7) | > > + SUN6I_DPHY_ANA0_REG_SFB(2)); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA1_REG, > > + SUN6I_DPHY_ANA1_REG_SVTT(4)); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA4_REG, > > + SUN6I_DPHY_ANA4_REG_DMPLVC | > > + SUN6I_DPHY_ANA4_REG_DMPLVD(1)); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA2_REG, > > + SUN6I_DPHY_ANA2_REG_ENIB); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA3_REG, > > + SUN6I_DPHY_ANA3_EN_LDOR | > > + SUN6I_DPHY_ANA3_EN_LDOC | > > + SUN6I_DPHY_ANA3_EN_LDOD); > > + > > + /* > > + * Delay comes from the Allwinner BSP, likely for internal regulator > > + * ramp-up. > > + */ > > + udelay(3); > > + > > + value = SUN6I_DPHY_RX_CTL_EN_DBC | SUN6I_DPHY_RX_CTL_RX_CLK_FORCE; > > + > > + /* > > + * Rx data lane force-enable bits are used as regular RX enable by the > > + * Allwinner BSP. > > + */ > > + if (dphy->config.lanes >= 1) > > + value |= SUN6I_DPHY_RX_CTL_RX_D0_FORCE; > > + if (dphy->config.lanes >= 2) > > + value |= SUN6I_DPHY_RX_CTL_RX_D1_FORCE; > > + if (dphy->config.lanes >= 3) > > + value |= SUN6I_DPHY_RX_CTL_RX_D2_FORCE; > > + if (dphy->config.lanes == 4) > > + value |= SUN6I_DPHY_RX_CTL_RX_D3_FORCE; > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_RX_CTL_REG, value); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_GCTL_REG, > > + SUN6I_DPHY_GCTL_LANE_NUM(dphy->config.lanes) | > > + SUN6I_DPHY_GCTL_EN); > > + > > + return 0; > > +} > > + > > +static int sun6i_dphy_power_on(struct phy *phy) > > +{ > > + struct sun6i_dphy *dphy = phy_get_drvdata(phy); > > + > > + switch (dphy->submode) { > > + case PHY_MIPI_DPHY_SUBMODE_TX: > > + return sun6i_dphy_tx_power_on(dphy); > > + case PHY_MIPI_DPHY_SUBMODE_RX: > > + return sun6i_dphy_rx_power_on(dphy); > > + default: > > + return -EINVAL; > > + } > > +} > > + > > Can one call power_on before set_mode? I didn't find anything indicating this is illegal. What would happen here is that the D-PHY would be configured to PHY_MIPI_DPHY_SUBMODE_TX (submode == 0) at power-on if set_mode is not called before. I think it's fair to expect that it's too late to change the mode once the PHY was powered on. Maybe we should return -EBUSY on set_mode when power on was already requested? > > static int sun6i_dphy_power_off(struct phy *phy) > > { > > struct sun6i_dphy *dphy = phy_get_drvdata(phy); > > > > - regmap_update_bits(dphy->regs, SUN6I_DPHY_ANA1_REG, > > - SUN6I_DPHY_ANA1_REG_VTTMODE, 0); > > + regmap_write(dphy->regs, SUN6I_DPHY_GCTL_REG, 0); > > + > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA0_REG, 0); > > + regmap_write(dphy->regs, SUN6I_DPHY_ANA1_REG, 0); > > This looks like a change that should be mentioned (or in a separate > patch). Right, this is a general change that applies to both Tx and Rx to cut-off the internal regulators. It's not directly related to this change so I think making it a preliminary patch would make sense. Thanks for the review! Paul -- Paul Kocialkowski, Bootlin Embedded Linux and kernel engineering https://bootlin.com
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