path: root/drivers/gpu/drm/armada/armada_crtc.c

/*
 * Copyright (C) 2012 Russell King
 *  Rewritten from the dovefb driver, and Armada510 manuals.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/clk.h>
#include <drm/drmP.h>
#include <drm/drm_crtc_helper.h>
#include "armada_crtc.h"
#include "armada_drm.h"
#include "armada_fb.h"
#include "armada_gem.h"
#include "armada_hw.h"

struct armada_frame_work {
	struct drm_pending_vblank_event *event;
	struct armada_regs regs[4];
	struct drm_framebuffer *old_fb;
};

enum csc_mode {
	CSC_AUTO = 0,
	CSC_YUV_CCIR601 = 1,
	CSC_YUV_CCIR709 = 2,
	CSC_RGB_COMPUTER = 1,
	CSC_RGB_STUDIO = 2,
};

/*
 * A note about interlacing.  Let's consider HDMI 1920x1080i.
 * The timing parameters we have from X are:
 *  Hact HsyA HsyI Htot  Vact VsyA VsyI Vtot
 *  1920 2448 2492 2640  1080 1084 1094 1125
 * Which get translated to:
 *  Hact HsyA HsyI Htot  Vact VsyA VsyI Vtot
 *  1920 2448 2492 2640   540  542  547  562
 *
 * This is how it is defined by CEA-861-D - line and pixel numbers are
 * referenced to the rising edge of VSYNC and HSYNC.  Total clocks per
 * line: 2640.  The odd frame, the first active line is at line 21, and
 * the even frame, the first active line is 584.
 *
 * LN:    560     561     562     563             567     568    569
 * DE:    ~~~|____________________________//__________________________
 * HSYNC: ____|~|_____|~|_____|~|_____|~|_//__|~|_____|~|_____|~|_____
 * VSYNC: _________________________|~~~~~~//~~~~~~~~~~~~~~~|__________
 *  22 blanking lines.  VSYNC at 1320 (referenced to the HSYNC rising edge).
 *
 * LN:    1123   1124    1125      1               5       6      7
 * DE:    ~~~|____________________________//__________________________
 * HSYNC: ____|~|_____|~|_____|~|_____|~|_//__|~|_____|~|_____|~|_____
 * VSYNC: ____________________|~~~~~~~~~~~//~~~~~~~~~~|_______________
 *  23 blanking lines
 *
 * The Armada LCD Controller line and pixel numbers are, like X timings,
 * referenced to the top left of the active frame.
 *
 * So, translating these to our LCD controller:
 *  Odd frame, 563 total lines, VSYNC at line 543-548, pixel 1128.
 *  Even frame, 562 total lines, VSYNC at line 542-547, pixel 2448.
 * Note: Vsync front porch remains constant!
 *
 * if (odd_frame) {
 *   vtotal = mode->crtc_vtotal + 1;
 *   vbackporch = mode->crtc_vsync_start - mode->crtc_vdisplay + 1;
 *   vhorizpos = mode->crtc_hsync_start - mode->crtc_htotal / 2
 * } else {
 *   vtotal = mode->crtc_vtotal;
 *   vbackporch = mode->crtc_vsync_start - mode->crtc_vdisplay;
 *   vhorizpos = mode->crtc_hsync_start;
 * }
 * vfrontporch = mode->crtc_vtotal - mode->crtc_vsync_end;
 *
 * So, we need to reprogram these registers on each vsync event:
 *  LCD_SPU_V_PORCH, LCD_SPU_ADV_REG, LCD_SPUT_V_H_TOTAL
 *
 * Note: we do not use the frame done interrupts because these appear
 * to happen too early, and lead to jitter on the display (presumably
 * they occur at the end of the last active line, before the vsync back
 * porch, which we're reprogramming.)
 */

void
armada_drm_crtc_update_regs(struct armada_crtc *dcrtc, struct armada_regs *regs)
{
	while (regs->offset != ~0) {
		void __iomem *reg = dcrtc->base + regs->offset;
		uint32_t val;

		val = regs->mask;
		if (val != 0)
			val &= readl_relaxed(reg);
		writel_relaxed(val | regs->val, reg);
		++regs;
	}
}

#define dpms_blanked(dpms)	((dpms) != DRM_MODE_DPMS_ON)

static void armada_drm_crtc_update(struct armada_crtc *dcrtc)
{
	uint32_t dumb_ctrl;

	dumb_ctrl = dcrtc->cfg_dumb_ctrl;

	if (!dpms_blanked(dcrtc->dpms))
		dumb_ctrl |= CFG_DUMB_ENA;

	/*
	 * When the dumb interface isn't in DUMB24_RGB888_0 mode, it might
	 * be using SPI or GPIO.  If we set this to DUMB_BLANK, we will
	 * force LCD_D[23:0] to output blank color, overriding the GPIO or
	 * SPI usage.  So leave it as-is unless in DUMB24_RGB888_0 mode.
	 */
	if (dpms_blanked(dcrtc->dpms) &&
	    (dumb_ctrl & DUMB_MASK) == DUMB24_RGB888_0) {
		dumb_ctrl &= ~DUMB_MASK;
		dumb_ctrl |= DUMB_BLANK;
	}

	/*
	 * The documentation doesn't indicate what the normal state of
	 * the sync signals are.  Sebastian Hesselbart kindly probed
	 * these signals on his board to determine their state.
	 *
	 * The non-inverted state of the sync signals is active high.
	 * Setting these bits makes the appropriate signal active low.
	 */
	if (dcrtc->crtc.mode.flags & DRM_MODE_FLAG_NCSYNC)
		dumb_ctrl |= CFG_INV_CSYNC;
	if (dcrtc->crtc.mode.flags & DRM_MODE_FLAG_NHSYNC)
		dumb_ctrl |= CFG_INV_HSYNC;
	if (dcrtc->crtc.mode.flags & DRM_MODE_FLAG_NVSYNC)
		dumb_ctrl |= CFG_INV_VSYNC;

	if (dcrtc->dumb_ctrl != dumb_ctrl) {
		dcrtc->dumb_ctrl = dumb_ctrl;
		writel_relaxed(dumb_ctrl, dcrtc->base + LCD_SPU_DUMB_CTRL);
	}
}

static unsigned armada_drm_crtc_calc_fb(struct drm_framebuffer *fb,
	int x, int y, struct armada_regs *regs, bool interlaced)
{
	struct armada_gem_object *obj = drm_fb_obj(fb);
	unsigned pitch = fb->pitches[0];
	unsigned offset = y * pitch + x * fb->bits_per_pixel / 8;
	uint32_t addr_odd, addr_even;
	unsigned i = 0;

	DRM_DEBUG_DRIVER("pitch %u x %d y %d bpp %d\n",
		pitch, x, y,