drm/etnaviv: disable MLCG and pulse eater on GPU reset

Module level clock gating and the pulse eater might interfere with
the GPU reset, as they both have the potential to stop the clock
and thus reset propagation to parts of the GPU.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Christian Gmeiner <cgmeiner@igalia.com>

Author: lynxeye-dev

drivers/gpu/drm/etnaviv/etnaviv_gpu.c

@@ -513,8 +513,19 @@ static int etnaviv_hw_reset(struct etnaviv_gpu *gpu)
 	timeout = jiffies + msecs_to_jiffies(1000);
 
 	while (time_is_after_jiffies(timeout)) {
-		/* enable clock */
 		unsigned int fscale = 1 << (6 - gpu->freq_scale);
+		u32 pulse_eater = 0x01590880;
+
+		/* disable clock gating */
+		gpu_write_power(gpu, VIVS_PM_POWER_CONTROLS, 0x0);
+
+		/* disable pulse eater */
+		pulse_eater |= BIT(17);
+		gpu_write_power(gpu, VIVS_PM_PULSE_EATER, pulse_eater);
+		pulse_eater |= BIT(0);
+		gpu_write_power(gpu, VIVS_PM_PULSE_EATER, pulse_eater);
+
+		/* enable clock */
 		control = VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(fscale);
 		etnaviv_gpu_load_clock(gpu, control);