path: root/drivers/gpu/drm/mcde/mcde_display.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2018 Linus Walleij <linus.walleij@linaro.org>
 * Parts of this file were based on the MCDE driver by Marcus Lorentzon
 * (C) ST-Ericsson SA 2013
 */
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dma-buf.h>

#include <drm/drm_device.h>
#include <drm/drm_fb_cma_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_simple_kms_helper.h>
#include <drm/drm_vblank.h>
#include <video/mipi_display.h>

#include "mcde_drm.h"
#include "mcde_display_regs.h"

enum mcde_fifo {
	MCDE_FIFO_A,
	MCDE_FIFO_B,
	/* TODO: implement FIFO C0 and FIFO C1 */
};

enum mcde_channel {
	MCDE_CHANNEL_0 = 0,
	MCDE_CHANNEL_1,
	MCDE_CHANNEL_2,
	MCDE_CHANNEL_3,
};

enum mcde_extsrc {
	MCDE_EXTSRC_0 = 0,
	MCDE_EXTSRC_1,
	MCDE_EXTSRC_2,
	MCDE_EXTSRC_3,
	MCDE_EXTSRC_4,
	MCDE_EXTSRC_5,
	MCDE_EXTSRC_6,
	MCDE_EXTSRC_7,
	MCDE_EXTSRC_8,
	MCDE_EXTSRC_9,
};

enum mcde_overlay {
	MCDE_OVERLAY_0 = 0,
	MCDE_OVERLAY_1,
	MCDE_OVERLAY_2,
	MCDE_OVERLAY_3,
	MCDE_OVERLAY_4,
	MCDE_OVERLAY_5,
};

enum mcde_dsi_formatter {
	MCDE_DSI_FORMATTER_0 = 0,
	MCDE_DSI_FORMATTER_1,
	MCDE_DSI_FORMATTER_2,
};

void mcde_display_irq(struct mcde *mcde)
{
	u32 mispp, misovl, mischnl;
	bool vblank = false;

	/* Handle display IRQs */
	mispp = readl(mcde->regs + MCDE_MISPP);
	misovl = readl(mcde->regs + MCDE_MISOVL);
	mischnl = readl(mcde->regs + MCDE_MISCHNL);

	/*
	 * Handle IRQs from the DSI link. All IRQs from the DSI links
	 * are just latched onto the MCDE IRQ line, so we need to traverse
	 * any active DSI masters and check if an IRQ is originating from
	 * them.
	 *
	 * TODO: Currently only one DSI link is supported.
	 */
	if (mcde_dsi_irq(mcde->mdsi)) {
		u32 val;

		/*
		 * In oneshot mode we do not send continuous updates
		 * to the display, instead we only push out updates when
		 * the update function is called, then we disable the
		 * flow on the channel once we get the TE IRQ.
		 */
		if (mcde->oneshot_mode) {
			spin_lock(&mcde->flow_lock);
			if (--mcde->flow_active == 0) {
				dev_dbg(mcde->dev, "TE0 IRQ\n");
				/* Disable FIFO A flow */
				val = readl(mcde->regs + MCDE_CRA0);
				val &= ~MCDE_CRX0_FLOEN;
				writel(val, mcde->regs + MCDE_CRA0);
			}
			spin_unlock(&mcde->flow_lock);
		}
	}

	/* Vblank from one of the channels */
	if (mispp & MCDE_PP_VCMPA) {
		dev_dbg(mcde->dev, "chnl A vblank IRQ\n");
		vblank = true;
	}
	if (mispp & MCDE_PP_VCMPB) {
		dev_dbg(mcde->dev, "chnl B vblank IRQ\n");
		vblank = true;
	}
	if (mispp & MCDE_PP_VCMPC0)
		dev_dbg(mcde->dev, "chnl C0 vblank IRQ\n");
	if (mispp & MCDE_PP_VCMPC1)
		dev_dbg(mcde->dev, "chnl C1 vblank IRQ\n");
	if (mispp & MCDE_PP_VSCC0)
		dev_dbg(mcde->dev, "chnl C0 TE IRQ\n");
	if (mispp & MCDE_PP_VSCC1)
		dev_dbg(mcde->dev, "chnl C1 TE IRQ\n");
	writel(mispp, mcde->regs + MCDE_RISPP);

	if (vblank)
		drm_crtc_handle_vblank(&mcde->pipe.crtc);

	if (misovl)
		dev_info(mcde->dev, "some stray overlay IRQ %08x\n", misovl);
	writel(misovl, mcde->regs + MCDE_RISOVL);

	if (mischnl)
		dev_info(mcde->dev, "some stray channel error IRQ %08x\n",
			 mischnl);
	writel(mischnl, mcde->regs + MCDE_RISCHNL);
}

void mcde_display_disable_irqs(struct mcde *mcde)
{
	/* Disable all IRQs */
	writel(0, mcde->regs + MCDE_IMSCPP);
	writel(0, mcde->regs + MCDE_IMSCOVL);
	writel(0, mcde->regs + MCDE_IMSCCHNL);

	/* Clear any pending IRQs */
	writel(0xFFFFFFFF, mcde->regs + MCDE_RISPP);
	writel(0xFFFFFFFF, mcde->regs + MCDE_RISOVL);
	writel(0xFFFFFFFF<