diff options
Diffstat (limited to 'drivers/gpu/drm/stm/ltdc.c')
| -rw-r--r-- | drivers/gpu/drm/stm/ltdc.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 808d9fb627e9..61dd661aa0ac 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -148,6 +148,8 @@ #define IER_TERRIE BIT(2) /* Transfer ERRor Interrupt Enable */ #define IER_RRIE BIT(3) /* Register Reload Interrupt enable */ +#define CPSR_CYPOS GENMASK(15, 0) /* Current Y position */ + #define ISR_LIF BIT(0) /* Line Interrupt Flag */ #define ISR_FUIF BIT(1) /* Fifo Underrun Interrupt Flag */ #define ISR_TERRIF BIT(2) /* Transfer ERRor Interrupt Flag */ @@ -626,6 +628,49 @@ static void ltdc_crtc_disable_vblank(struct drm_crtc *crtc) reg_clear(ldev->regs, LTDC_IER, IER_LIE); } +bool ltdc_crtc_scanoutpos(struct drm_device *ddev, unsigned int pipe, + bool in_vblank_irq, int *vpos, int *hpos, + ktime_t *stime, ktime_t *etime, + const struct drm_display_mode *mode) +{ + struct ltdc_device *ldev = ddev->dev_private; + int line, vactive_start, vactive_end, vtotal; + + if (stime) + *stime = ktime_get(); + + /* The active area starts after vsync + front porch and ends + * at vsync + front porc + display size. + * The total height also include back porch. + * We have 3 possible cases to handle: + * - line < vactive_start: vpos = line - vactive_start and will be + * negative + * - vactive_start < line < vactive_end: vpos = line - vactive_start + * and will be positive + * - line > vactive_end: vpos = line - vtotal - vactive_start + * and will negative + * + * Computation for the two first cases are identical so we can + * simplify the code and only test if line > vactive_end + */ + line = reg_read(ldev->regs, LTDC_CPSR) & CPSR_CYPOS; + vactive_start = reg_read(ldev->regs, LTDC_BPCR) & BPCR_AVBP; + vactive_end = reg_read(ldev->regs, LTDC_AWCR) & AWCR_AAH; + vtotal = reg_read(ldev->regs, LTDC_TWCR) & TWCR_TOTALH; + + if (line > vactive_end) + *vpos = line - vtotal - vactive_start; + else + *vpos = line - vactive_start; + + *hpos = 0; + + if (etime) + *etime = ktime_get(); + + return true; +} + static const struct drm_crtc_funcs ltdc_crtc_funcs = { .destroy = drm_crtc_cleanup, .set_config = drm_atomic_helper_set_config, |