[Freedreno] db820c: Input signal Out of range

Ricardo Ribalda Delgado ricardo.ribalda at gmail.com
Mon Aug 13 08:54:57 UTC 2018


Hi Archit
On Sun, Aug 12, 2018 at 9:47 AM Archit Taneja <architt at codeaurora.org> wrote:
>
> Hi,
>
> On Friday 10 August 2018 12:08 PM, Ricardo Ribalda Delgado wrote:
> > Hello
> >
> > I have a screen that via edid expects the following modeline by
> > default via detailed mode:
> >
> > Modeline "1680x1050"x60.0  146.30  1680 1784 1960 2240  1050 1053 1059
> > 1089 +hsync -vsync
> >
> > When the card is configured to that modeline the screen cannot output
> > the image and shows the following error message: Input signal out of
> > range.
> >
> > I have tried with a different card and that exact modeline:
> >
> > xrandr --newmode fast 146.30  1680 1784 1960 2240  1050 1053 1059 1089
> > +hsync -vsync
> > xrandr --addmode HDMI-1 slow
> > xrandr --output HDMI-1 --mode fast
> >
> > and the screen works just fine.
> >
> >
> > If I just tweak down a bit the clock:
> > xrandr --newmode slow 146.25  1680 1784 1960 2240  1050 1053 1059 1089
> > +hsync -vsync
> > the screen shows an image as expected.
> >
> > I believe that there might be a misscalculation on the pll code. And I
> > am printing the debug info from:
> > drivers/gpu/drm/msm/hdmi/hdmi_phy_8996.c
> >
> > The configuration that fails shows:
> >
> > [  138.553168] VCO freq: 8778000000
> > [  138.553172] fdata: 1463000000
> > [  138.553187] pix_clk: 146300000
> > [  138.555447] tmds clk: 146300000
> > [  138.558336] HSCLK_SEL: 1
> > [  138.561277] DEC_START: 114
> > [  138.564316] DIV_FRAC_START: 311296
> > [  138.567080] PLL_CPCTRL: 11
> > [  138.569614] PLL_RCTRL: 22
> > [  138.572996] PLL_CCTRL: 40
> > [  138.575698] INTEGLOOP_GAIN: 256
> > [  138.578366] TX_BAND: 0
> > [  138.580986] PLL_CMP: 7802
> > [  138.583936] com_svs_mode_clk_sel = 0x2
> > [  138.586351] com_hsclk_sel = 0x21
> > [  138.589067] com_lock_cmp_en = 0x0
> > [  138.592704] com_pll_cctrl_mode0 = 0x28
> > [  138.596089] com_pll_rctrl_mode0 = 0x16
> > [  138.599286] com_cp_ctrl_mode0 = 0xb
> > [  138.602955] com_dec_start_mode0 = 0x72
> > [  138.606678] com_div_frac_start1_mode0 = 0x0
> > [  138.610064] com_div_frac_start2_mode0 = 0xc0
> > [  138.613894] com_div_frac_start3_mode0 = 0x4
> > [  138.617964] com_integloop_gain0_mode0 = 0x0
> > [  138.622478] com_integloop_gain1_mode0 = 0x1
> > [  138.626393] com_lock_cmp1_mode0 = 0x7a
> > [  138.630550] com_lock_cmp2_mode0 = 0x1e
> > [  138.634719] com_lock_cmp3_mode0 = 0x0
> > [  138.638545] com_core_clk_en = 0x2c
> > [  138.642271] com_coreclk_div = 0x5
> > [  138.646001] phy_mode = 0x0
> > [  138.649308] tx_l0_lane_mode = 0x43
> > [  138.652684] tx_l2_lane_mode = 0x43
> > [  138.655275] tx_l0_tx_band = 0x4
> > [  138.658679] tx_l0_tx_drv_lvl = 0x25
> > [  138.662070] tx_l0_tx_emp_post1_lvl = 0x23
> > [  138.665101] tx_l0_vmode_ctrl1 = 0x0
> > [  138.668571] tx_l0_vmode_ctrl2 = 0xd
> > [  138.672747] tx_l1_tx_band = 0x4
> > [  138.676037] tx_l1_tx_drv_lvl = 0x25
> > [  138.679493] tx_l1_tx_emp_post1_lvl = 0x23
> > [  138.682633] tx_l1_vmode_ctrl1 = 0x0
> > [  138.686117] tx_l1_vmode_ctrl2 = 0xd
> > [  138.690272] tx_l2_tx_band = 0x4
> > [  138.693571] tx_l2_tx_drv_lvl = 0x25
> > [  138.697050] tx_l2_tx_emp_post1_lvl = 0x23
> > [  138.700168] tx_l2_vmode_ctrl1 = 0x0
> > [  138.703641] tx_l2_vmode_ctrl2 = 0xd
> > [  138.707816] tx_l3_tx_band = 0x4
> > [  138.711092] tx_l3_tx_drv_lvl = 0x25
> > [  138.714577] tx_l3_tx_emp_post1_lvl = 0x23
> > [  138.717705] tx_l3_vmode_ctrl1 = 0x0
> > [  138.721182] tx_l3_vmode_ctrl2 = 0x0
> >
> > and the configuration that works:
> >
> > [   62.936970] VCO freq: 8775000000
> > [   62.936976] fdata: 1462500000
> > [   62.936990] pix_clk: 146250000
> > [   62.939250] tmds clk: 146250000
> > [   62.942175] HSCLK_SEL: 1
> > [   62.945095] DEC_START: 114
> > [   62.948117] DIV_FRAC_START: 270336
> > [   62.950881] PLL_CPCTRL: 11
> > [   62.953421] PLL_RCTRL: 22
> > [   62.956798] PLL_CCTRL: 40
> > [   62.959475] INTEGLOOP_GAIN: 256
> > [   62.962179] TX_BAND: 0
> > [   62.964785] PLL_CMP: 7799
> > [   62.967738] com_svs_mode_clk_sel = 0x2
> > [   62.970153] com_hsclk_sel = 0x21
> > [   62.972862] com_lock_cmp_en = 0x0
> > [   62.976506] com_pll_cctrl_mode0 = 0x28
> > [   62.979893] com_pll_rctrl_mode0 = 0x16
> > [   62.983088] com_cp_ctrl_mode0 = 0xb
> > [   62.986749] com_dec_start_mode0 = 0x72
> > [   62.990480] com_div_frac_start1_mode0 = 0x0
> > [   62.993868] com_div_frac_start2_mode0 = 0x20
> > [   62.997688] com_div_frac_start3_mode0 = 0x4
> > [   63.001769] com_integloop_gain0_mode0 = 0x0
> > [   63.006281] com_integloop_gain1_mode0 = 0x1
> > [   63.010189] com_lock_cmp1_mode0 = 0x77
> > [   63.014354] com_lock_cmp2_mode0 = 0x1e
> > [   63.018521] com_lock_cmp3_mode0 = 0x0
> > [   63.022338] com_core_clk_en = 0x2c
> > [   63.026072] com_coreclk_div = 0x5
> > [   63.029804] phy_mode = 0x0
> > [   63.033103] tx_l0_lane_mode = 0x43
> > [   63.036488] tx_l2_lane_mode = 0x43
> > [   63.039078] tx_l0_tx_band = 0x4
> > [   63.042479] tx_l0_tx_drv_lvl = 0x25
> > [   63.045864] tx_l0_tx_emp_post1_lvl = 0x23
> > [   63.048901] tx_l0_vmode_ctrl1 = 0x0
> > [   63.052375] tx_l0_vmode_ctrl2 = 0xd
> > [   63.056541] tx_l1_tx_band = 0x4
> > [   63.059840] tx_l1_tx_drv_lvl = 0x25
> > [   63.063295] tx_l1_tx_emp_post1_lvl = 0x23
> > [   63.066437] tx_l1_vmode_ctrl1 = 0x0
> > [   63.069908] tx_l1_vmode_ctrl2 = 0xd
> > [   63.074075] tx_l2_tx_band = 0x4
> > [   63.077373] tx_l2_tx_drv_lvl = 0x25
> > [   63.080844] tx_l2_tx_emp_post1_lvl = 0x23
> > [   63.083971] tx_l2_vmode_ctrl1 = 0x0
> > [   63.087428] tx_l2_vmode_ctrl2 = 0xd
> > [   63.091609] tx_l3_tx_band = 0x4
> > [   63.094906] tx_l3_tx_drv_lvl = 0x25
> > [   63.098379] tx_l3_tx_emp_post1_lvl = 0x23
> > [   63.101505] tx_l3_vmode_ctrl1 = 0x0
> > [   63.104979] tx_l3_vmode_ctrl2 = 0x0
> >
> > Unfortunately I do not have the documentation of the pll to validade
> > any of the two setups.
>
> I'm not sure if there is any public documentation of the hardware
> registers for 8x96. I'd myself mostly ported this code from the
> downstream hdmi PLL driver (the 8996_v3 code in particular):
>
> https://source.codeaurora.org/quic/la/kernel/msm-3.18/tree/drivers/clk/msm/mdss/mdss-hdmi-pll-8996.c?h=msm-3.18
>
> The PLL seems to be getting locked for both cases. But for some reason,
> when trying to configure it for 146.30 Mhz, it's generating a
> wayward enough value for the monitor to reject it.
>
> I looked at the logs, and the configurations match what both the
> upstream and downstream drivers are trying to do.
>
> The main differences between the configurations seem to be the
> fractional component calculation and the computation of PLL_CMP.
>
>  From my experience, minor changes in the fractional component don't
> calculation doesn't cause too much of a difference.
>
> As an experiment, you could try to forcibly set the PLL_CMP value to
> 7799 in the non-working case to check if that's causing the issue.
> We could then try to find out from someone within Qualcomm if there's
> a better way to compute this parameter.

forcing PLL_CMP to 7799 worked :)


Now trying with a different monitor. And it also fails :S This time
with this modeline

Modeline "1680x1050"x59.9  119.00  1680 1728 1760 1840  1050 1053 1059
1080 +hsync -vsync (64.7 kHz eP)

[    6.362578] VCO freq: 9520000000
[    6.362582] fdata: 2380000000
[    6.362584] pix_clk: 119000000
[    6.362586] tmds clk: 119000000
[    6.362588] HSCLK_SEL: 8
[    6.362589] DEC_START: 123
[    6.362591] DIV_FRAC_START: 1004885
[    6.362592] PLL_CPCTRL: 11
[    6.362594] PLL_RCTRL: 22
[    6.362596] PLL_CCTRL: 40
[    6.362597] INTEGLOOP_GAIN: 256
[    6.362599] TX_BAND: 1
[    6.362600] PLL_CMP: 12692
[    6.362602] com_svs_mode_clk_sel = 0x2
[    6.362604] com_hsclk_sel = 0x28
[    6.362605] com_lock_cmp_en = 0x0
[    6.362607] com_pll_cctrl_mode0 = 0x28
[    6.362608] com_pll_rctrl_mode0 = 0x16
[    6.362610] com_cp_ctrl_mode0 = 0xb
[    6.362611] com_dec_start_mode0 = 0x7b
[    6.362613] com_div_frac_start1_mode0 = 0x55
[    6.362615] com_div_frac_start2_mode0 = 0x55
[    6.362616] com_div_frac_start3_mode0 = 0xf
[    6.362617] com_integloop_gain0_mode0 = 0x0
[    6.362619] com_integloop_gain1_mode0 = 0x1
[    6.362621] com_lock_cmp1_mode0 = 0x94
[    6.362622] com_lock_cmp2_mode0 = 0x31
[    6.362624] com_lock_cmp3_mode0 = 0x0
[    6.362625] com_core_clk_en = 0x2c
[    6.362627] com_coreclk_div = 0x5
[    6.362628] phy_mode = 0x0
[    6.362630] tx_l0_lane_mode = 0x43
[    6.362631] tx_l2_lane_mode = 0x43
[    6.362633] tx_l0_tx_band = 0x5
[    6.362635] tx_l0_tx_drv_lvl = 0x25
[    6.362636] tx_l0_tx_emp_post1_lvl = 0x23
[    6.362638] tx_l0_vmode_ctrl1 = 0x0
[    6.362640] tx_l0_vmode_ctrl2 = 0xd
[    6.362641] tx_l1_tx_band = 0x5
[    6.362643] tx_l1_tx_drv_lvl = 0x25
[    6.362644] tx_l1_tx_emp_post1_lvl = 0x23
[    6.362646] tx_l1_vmode_ctrl1 = 0x0
[    6.362647] tx_l1_vmode_ctrl2 = 0xd
[    6.362649] tx_l2_tx_band = 0x5
[    6.362650] tx_l2_tx_drv_lvl = 0x25
[    6.362652] tx_l2_tx_emp_post1_lvl = 0x23
[    6.362653] tx_l2_vmode_ctrl1 = 0x0
[    6.362655] tx_l2_vmode_ctrl2 = 0xd
[    6.362656] tx_l3_tx_band = 0x5
[    6.362658] tx_l3_tx_drv_lvl = 0x25
[    6.362659] tx_l3_tx_emp_post1_lvl = 0x23
[    6.362661] tx_l3_vmode_ctrl1 = 0x0
[    6.362662] tx_l3_vmode_ctrl2 = 0x0
[    6.362663] Disabling PHY
[    6.363531] Waiting for PLL lock
[    6.364455] HDMI PLL is locked
[    6.364471] Waiting for PHY ready
[    6.364473] PHY is ready

I have tried subtracting 3 to PLL_CMP, but that did not work

also tried with 12687, which failed.

On the other hand, the standard cvt for 1680x1050 at 60Hz worked just
fine (like before)

Thanks!


>
> Thanks,
> Archit
>
>
> >
> > Where can I find that doc?
> > Any ideas of how to proceed?
> >
> >
> > Thanks!
> >



--
Ricardo Ribalda


More information about the Freedreno mailing list