diff options
| author | Adam Ford <aford173@gmail.com> | 2024-10-26 08:19:59 -0500 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2024-12-08 21:21:20 +0530 |
| commit | d567679f2b6a8bcea20589bbea6488c0236886cd (patch) | |
| tree | 93a2d21ed862530391601787a2fa1ee744856a0a | |
| parent | 1b9b8b159601d174526ce1c3a62ebe3a7286003b (diff) | |
phy: freescale: fsl-samsung-hdmi: Clean up fld_tg_code calculation
Currently, the calcuation for fld_tg_code is based on a lookup table,
but there are gaps in the lookup table, and frequencies in these
gaps may not properly use the correct divider. Based on the description
of FLD_CK_DIV, the internal PLL frequency should be less than 50 MHz,
so directly calcuate the value of FLD_CK_DIV from pixclk.
This allow for proper calcuation of any pixel clock and eliminates a
few gaps in the LUT.
Since the value of the int_pllclk is in Hz, do the fixed-point
math in Hz to achieve a more accurate value and reduces the complexity
of the caluation to 24MHz * (256 / int_pllclk).
Fixes: 6ad082bee902 ("phy: freescale: add Samsung HDMI PHY")
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Link: https://lore.kernel.org/r/20241026132014.73050-3-aford173@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/phy/freescale/phy-fsl-samsung-hdmi.c | 32 |
1 files changed, 11 insertions, 21 deletions
diff --git a/drivers/phy/freescale/phy-fsl-samsung-hdmi.c b/drivers/phy/freescale/phy-fsl-samsung-hdmi.c index 121f67455cec..5eac70a1e858 100644 --- a/drivers/phy/freescale/phy-fsl-samsung-hdmi.c +++ b/drivers/phy/freescale/phy-fsl-samsung-hdmi.c @@ -331,25 +331,17 @@ fsl_samsung_hdmi_phy_configure_pll_lock_det(struct fsl_samsung_hdmi_phy *phy, { u32 pclk = cfg->pixclk; u32 fld_tg_code; - u32 pclk_khz; - u8 div = 1; - - switch (cfg->pixclk) { - case 22250000 ... 47500000: - div = 1; - break; - case 50349650 ... 99000000: - div = 2; - break; - case 100699300 ... 198000000: - div = 4; - break; - case 205000000 ... 297000000: - div = 8; - break; + u32 int_pllclk; + u8 div; + + /* Find int_pllclk speed */ + for (div = 0; div < 4; div++) { + int_pllclk = pclk / (1 << div); + if (int_pllclk < (50 * MHZ)) + break; } - writeb(FIELD_PREP(REG12_CK_DIV_MASK, ilog2(div)), phy->regs + PHY_REG(12)); + writeb(FIELD_PREP(REG12_CK_DIV_MASK, div), phy->regs + PHY_REG(12)); /* * Calculation for the frequency lock detector target code (fld_tg_code) @@ -362,10 +354,8 @@ fsl_samsung_hdmi_phy_configure_pll_lock_det(struct fsl_samsung_hdmi_phy *phy, * settings rounding up always too. TODO: Check if that is * correct. */ - pclk /= div; - pclk_khz = pclk / 1000; - fld_tg_code = 256 * 1000 * 1000 / pclk_khz * 24; - fld_tg_code = DIV_ROUND_UP(fld_tg_code, 1000); + + fld_tg_code = DIV_ROUND_UP(24 * MHZ * 256, int_pllclk); /* FLD_TOL and FLD_RP_CODE taken from downstream driver */ writeb(FIELD_PREP(REG13_TG_CODE_LOW_MASK, fld_tg_code), |