lsdc_irq.c

 1// SPDX-License-Identifier: GPL-2.0+
 2/*
 3 * Copyright (C) 2023 Loongson Technology Corporation Limited
 4 */
 5
 6#include <drm/drm_print.h>
 7#include <drm/drm_vblank.h>
 8
 9#include "lsdc_irq.h"
10
11/*
12 * For the DC in LS7A2000, clearing interrupt status is achieved by
13 * write "1" to LSDC_INT_REG.
14 *
15 * For the DC in LS7A1000, clear interrupt status is achieved by write "0"
16 * to LSDC_INT_REG.
17 *
18 * Two different hardware engineers modify it as their will.
19 */
20
21irqreturn_t ls7a2000_dc_irq_handler(int irq, void *arg)
22{
23	struct drm_device *ddev = arg;
24	struct lsdc_device *ldev = to_lsdc(ddev);
25	u32 val;
26
27	/* Read the interrupt status */
28	val = lsdc_rreg32(ldev, LSDC_INT_REG);
29	if ((val & INT_STATUS_MASK) == 0) {
30		drm_warn(ddev, "no interrupt occurs\n");
31		return IRQ_NONE;
32	}
33
34	ldev->irq_status = val;
35
36	/* write "1" to clear the interrupt status */
37	lsdc_wreg32(ldev, LSDC_INT_REG, val);
38
39	if (ldev->irq_status & INT_CRTC0_VSYNC)
40		drm_handle_vblank(ddev, 0);
41
42	if (ldev->irq_status & INT_CRTC1_VSYNC)
43		drm_handle_vblank(ddev, 1);
44
45	return IRQ_HANDLED;
46}
47
48/* For the DC in LS7A1000 and LS2K1000 */
49irqreturn_t ls7a1000_dc_irq_handler(int irq, void *arg)
50{
51	struct drm_device *ddev = arg;
52	struct lsdc_device *ldev = to_lsdc(ddev);
53	u32 val;
54
55	/* Read the interrupt status */
56	val = lsdc_rreg32(ldev, LSDC_INT_REG);
57	if ((val & INT_STATUS_MASK) == 0) {
58		drm_warn(ddev, "no interrupt occurs\n");
59		return IRQ_NONE;
60	}
61
62	ldev->irq_status = val;
63
64	/* write "0" to clear the interrupt status */
65	val &= ~(INT_CRTC0_VSYNC | INT_CRTC1_VSYNC);
66	lsdc_wreg32(ldev, LSDC_INT_REG, val);
67
68	if (ldev->irq_status & INT_CRTC0_VSYNC)
69		drm_handle_vblank(ddev, 0);
70
71	if (ldev->irq_status & INT_CRTC1_VSYNC)
72		drm_handle_vblank(ddev, 1);
73
74	return IRQ_HANDLED;
75}