diff options
Diffstat (limited to 'drivers/gpu/drm/rcar-du/rcar_du_crtc.c')
| -rw-r--r-- | drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 37 |
1 files changed, 27 insertions, 10 deletions
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index 63c32b3582fb..d82aa67162c6 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -13,6 +13,7 @@ #include <linux/clk.h> #include <linux/mutex.h> +#include <linux/sys_soc.h> #include <drm/drmP.h> #include <drm/drm_atomic.h> @@ -129,10 +130,8 @@ static void rcar_du_dpll_divider(struct rcar_du_crtc *rcrtc, for (fdpll = 1; fdpll < 32; fdpll++) { unsigned long output; - /* 1/2 (FRQSEL=1) for duty rate 50% */ output = input * (n + 1) / (m + 1) - / (fdpll + 1) / 2; - + / (fdpll + 1); if (output >= 400000000) continue; @@ -158,6 +157,11 @@ done: best_diff); } +static const struct soc_device_attribute rcar_du_r8a7795_es1[] = { + { .soc_id = "r8a7795", .revision = "ES1.*" }, + { /* sentinel */ } +}; + static void rcar_du_crtc_set_display_timing(struct rcar_du_crtc *rcrtc) { const struct drm_display_mode *mode = &rcrtc->crtc.state->adjusted_mode; @@ -186,7 +190,20 @@ static void rcar_du_crtc_set_display_timing(struct rcar_du_crtc *rcrtc) extclk = clk_get_rate(rcrtc->extclock); if (rcdu->info->dpll_ch & (1 << rcrtc->index)) { - rcar_du_dpll_divider(rcrtc, &dpll, extclk, mode_clock); + unsigned long target = mode_clock; + + /* + * The H3 ES1.x exhibits dot clock duty cycle stability + * issues. We can work around them by configuring the + * DPLL to twice the desired frequency, coupled with a + * /2 post-divider. This isn't needed on other SoCs and + * breaks HDMI output on M3-W for a currently unknown + * reason, so restrict the workaround to H3 ES1.x. + */ + if (soc_device_match(rcar_du_r8a7795_es1)) + target *= 2; + + rcar_du_dpll_divider(rcrtc, &dpll, extclk, target); extclk = dpll.output; } @@ -198,8 +215,6 @@ static void rcar_du_crtc_set_display_timing(struct rcar_du_crtc *rcrtc) if (abs((long)extrate - (long)mode_clock) < abs((long)rate - (long)mode_clock)) { - dev_dbg(rcrtc->group->dev->dev, - "crtc%u: using external clock\n", rcrtc->index); if (rcdu->info->dpll_ch & (1 << rcrtc->index)) { u32 dpllcr = DPLLCR_CODE | DPLLCR_CLKE @@ -216,12 +231,14 @@ static void rcar_du_crtc_set_display_timing(struct rcar_du_crtc *rcrtc) rcar_du_group_write(rcrtc->group, DPLLCR, dpllcr); - - escr = ESCR_DCLKSEL_DCLKIN | 1; - } else { - escr = ESCR_DCLKSEL_DCLKIN | extdiv; } + + escr = ESCR_DCLKSEL_DCLKIN | extdiv; } + + dev_dbg(rcrtc->group->dev->dev, + "mode clock %lu extrate %lu rate %lu ESCR 0x%08x\n", + mode_clock, extrate, rate, escr); } rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? ESCR2 : ESCR, |