// SPDX-License-Identifier: GPL-2.0
/*
* bcm2835 sdhost driver.
*
* The 2835 has two SD controllers: The Arasan sdhci controller
* (supported by the iproc driver) and a custom sdhost controller
* (supported by this driver).
*
* The sdhci controller supports both sdcard and sdio. The sdhost
* controller supports the sdcard only, but has better performance.
* Also note that the rpi3 has sdio wifi, so driving the sdcard with
* the sdhost controller allows to use the sdhci controller for wifi
* support.
*
* The configuration is done by devicetree via pin muxing. Both
* SD controller are available on the same pins (2 pin groups = pin 22
* to 27 + pin 48 to 53). So it's possible to use both SD controllers
* at the same time with different pin groups.
*
* Author: Phil Elwell <phil@raspberrypi.org>
* Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
*
* Based on
* mmc-bcm2835.c by Gellert Weisz
* which is, in turn, based on
* sdhci-bcm2708.c by Broadcom
* sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko
* sdhci.c and sdhci-pci.c by Pierre Ossman
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/highmem.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/time.h>
#include <linux/workqueue.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sd.h>
#define SDCMD 0x00 /* Command to SD card - 16 R/W */
#define SDARG 0x04 /* Argument to SD card - 32 R/W */
#define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
#define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */
#define SDRSP0 0x10 /* SD card response (31:0) - 32 R */
#define SDRSP1 0x14 /* SD card response (63:32) - 32 R */
#define SDRSP2 0x18 /*
