linux/drivers/mmc/host/sdhci-esdhc.h

/*
 * Freescale eSDHC controller driver generics for OF and pltfm.
 *
 * Copyright (c) 2007 Freescale Semiconductor, Inc.
 * Copyright (c) 2009 MontaVista Software, Inc.
 * Copyright (c) 2010 Pengutronix e.K.
 *   Author: Wolfram Sang <w.sang@pengutronix.de>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License.
 */

#ifndef _DRIVERS_MMC_SDHCI_ESDHC_H
#define _DRIVERS_MMC_SDHCI_ESDHC_H

/*
 * Ops and quirks for the Freescale eSDHC controller.
 */

#define ESDHC_DEFAULT_QUIRKS	(SDHCI_QUIRK_FORCE_BLK_SZ_2048 | \
				SDHCI_QUIRK_NO_BUSY_IRQ | \
				SDHCI_QUIRK_NONSTANDARD_CLOCK | \
				SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | \
				SDHCI_QUIRK_PIO_NEEDS_DELAY | \
				SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET)

#define ESDHC_SYSTEM_CONTROL	0x2c
#define ESDHC_CLOCK_MASK	0x0000fff0
#define ESDHC_PREDIV_SHIFT	8
#define ESDHC_DIVIDER_SHIFT	4
#define ESDHC_CLOCK_PEREN	0x00000004
#define ESDHC_CLOCK_HCKEN	0x00000002
#define ESDHC_CLOCK_IPGEN	0x00000001

/* pltfm-specific */
#define ESDHC_HOST_CONTROL_LE	0x20

/* OF-specific */
#define ESDHC_DMA_SYSCTL	0x40c
#define ESDHC_DMA_SNOOP		0x00000040

#define ESDHC_HOST_CONTROL_RES	0x05

static inline void esdhc_set_clock(struct sdhci_host *host, unsigned int clock)
{
	int pre_div = 2;
	int div = 1;
	u32 temp;

	temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
	temp &= ~(ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN
		| ESDHC_CLOCK_MASK);
	sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);

	if (clock == 0)
		goto out;

	while (host->max_clk / pre_div / 16 > clock && pre_div < 256)
		pre_div *= 2;

	while (host->max_clk / pre_div / div > clock && div < 16)
		div++;

	dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
		clock, host->max_clk / pre_div / div);

	pre_div >>= 1;
	div--;

	temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
	temp |= (ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN
		| (div << ESDHC_DIVIDER_SHIFT)
		| (pre_div << ESDHC_PREDIV_SHIFT));
	sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
	mdelay(1);
out:
	host->clock = clock;
}

#endif /* _DRIVERS_MMC_SDHCI_ESDHC_H */