Add i.MX23 MCI card support
Adding MCI card support for STM378x/i.MX23 CPUs. This is for reference only, as this architecture is currently not part of barebox (but will coming soon). Its tested on the i.MX23 based ChumbyOne. Signed-off-by: Juergen Beisert <jbe@pengutronix.de> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
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916a1ca70a
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@ -27,4 +27,11 @@ config MCI_INFO
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comment "--- MCI host drivers ---"
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config MCI_STM378X
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bool "i.MX23"
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depends on ARCH_STM
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help
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Enable this entry to add support to read and write SD cards on a
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i.MX23 based system.
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endif
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@ -1 +1,2 @@
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obj-$(CONFIG_MCI) += mci-core.o
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obj-$(CONFIG_MCI_STM378X) += stm378x.o
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@ -0,0 +1,699 @@
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/*
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* Copyright (C) 2010 Juergen Beisert, Pengutronix <jbe@pengutronix.de>
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*
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* This code is based on:
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*
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* Copyright (C) 2007 SigmaTel, Inc., Ioannis Kappas <ikappas@sigmatel.com>
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*
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* Portions copyright (C) 2003 Russell King, PXA MMCI Driver
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* Portions copyright (C) 2004-2005 Pierre Ossman, W83L51xD SD/MMC driver
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*
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* Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
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* Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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* MA 02111-1307 USA
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*/
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/**
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* @file
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* @brief MCI card host interface for i.MX23 CPU
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*/
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/* #define DEBUG */
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#include <common.h>
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#include <init.h>
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#include <mci.h>
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#include <errno.h>
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#include <clock.h>
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#include <asm/io.h>
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#include <asm/bitops.h>
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#include <mach/imx-regs.h>
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#include <mach/mci.h>
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#include <mach/clock.h>
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#define CLOCKRATE_MIN (1 * 1000 * 1000)
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#define CLOCKRATE_MAX (480 * 1000 * 1000)
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#define HW_SSP_CTRL0 0x000
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# define SSP_CTRL0_SFTRST (1 << 31)
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# define SSP_CTRL0_CLKGATE (1 << 30)
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# define SSP_CTRL0_RUN (1 << 29)
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# define SSP_CTRL0_LOCK_CS (1 << 29)
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# define SSP_CTRL0_READ (1 << 25)
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# define SSP_CTRL0_IGNORE_CRC (1 << 26)
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# define SSP_CTRL0_DATA_XFER (1 << 24)
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# define SSP_CTRL0_BUS_WIDTH(x) (((x) & 0x3) << 22)
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# define SSP_CTRL0_WAIT_FOR_IRQ (1 << 21)
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# define SSP_CTRL0_LONG_RESP (1 << 19)
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# define SSP_CTRL0_GET_RESP (1 << 17)
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# define SSP_CTRL0_ENABLE (1 << 16)
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# define SSP_CTRL0_XFER_COUNT(x) ((x) & 0xffff)
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#define HW_SSP_CMD0 0x010
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# define SSP_CMD0_SLOW_CLK (1 << 22)
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# define SSP_CMD0_CONT_CLK (1 << 21)
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# define SSP_CMD0_APPEND_8CYC (1 << 20)
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# define SSP_CMD0_BLOCK_SIZE(x) (((x) & 0xf) << 16)
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# define SSP_CMD0_BLOCK_COUNT(x) (((x) & 0xff) << 8)
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# define SSP_CMD0_CMD(x) ((x) & 0xff)
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#define HW_SSP_CMD1 0x020
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#define HW_SSP_COMPREF 0x030
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#define HW_SSP_COMPMASK 0x040
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#define HW_SSP_TIMING 0x050
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# define SSP_TIMING_TIMEOUT_MASK (0xffff0000)
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# define SSP_TIMING_TIMEOUT(x) ((x) << 16)
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# define SSP_TIMING_CLOCK_DIVIDE(x) (((x) & 0xff) << 8)
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# define SSP_TIMING_CLOCK_RATE(x) ((x) & 0xff)
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#define HW_SSP_CTRL1 0x060
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# define SSP_CTRL1_POLARITY (1 << 9)
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# define SSP_CTRL1_WORD_LENGTH(x) (((x) & 0xf) << 4)
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# define SSP_CTRL1_SSP_MODE(x) ((x) & 0xf)
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#define HW_SSP_DATA 0x070
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#define HW_SSP_SDRESP0 0x080
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#define HW_SSP_SDRESP1 0x090
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#define HW_SSP_SDRESP2 0x0A0
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#define HW_SSP_SDRESP3 0x0B0
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#define HW_SSP_STATUS 0x0C0
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# define SSP_STATUS_PRESENT (1 << 31)
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# define SSP_STATUS_SD_PRESENT (1 << 29)
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# define SSP_STATUS_CARD_DETECT (1 << 28)
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# define SSP_STATUS_RESP_CRC_ERR (1 << 16)
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# define SSP_STATUS_RESP_ERR (1 << 15)
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# define SSP_STATUS_RESP_TIMEOUT (1 << 14)
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# define SSP_STATUS_DATA_CRC_ERR (1 << 13)
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# define SSP_STATUS_TIMEOUT (1 << 12)
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# define SSP_STATUS_FIFO_OVRFLW (1 << 9)
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# define SSP_STATUS_FIFO_FULL (1 << 8)
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# define SSP_STATUS_FIFO_EMPTY (1 << 5)
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# define SSP_STATUS_FIFO_UNDRFLW (1 << 4)
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# define SSP_STATUS_CMD_BUSY (1 << 3)
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# define SSP_STATUS_DATA_BUSY (1 << 2)
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# define SSP_STATUS_BUSY (1 << 0)
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# define SSP_STATUS_ERROR (SSP_STATUS_FIFO_OVRFLW | SSP_STATUS_FIFO_UNDRFLW | \
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SSP_STATUS_RESP_CRC_ERR | SSP_STATUS_RESP_ERR | \
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SSP_STATUS_RESP_TIMEOUT | SSP_STATUS_DATA_CRC_ERR | SSP_STATUS_TIMEOUT)
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#define HW_SSP_DEBUG 0x100
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#define HW_SSP_VERSION 0x110
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struct stm_mci_host {
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unsigned clock; /* current clock speed in Hz ("0" if disabled) */
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#ifdef CONFIG_MCI_INFO
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unsigned f_min;
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unsigned f_max;
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#endif
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int bus_width:2; /* 0 = 1 bit, 1 = 4 bit, 2 = 8 bit */
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};
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/**
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* Get MCI cards response if defined for the type of command
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* @param hw_dev Host interface device instance
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* @param cmd Command description
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* @return Response bytes count, -EINVAL for unsupported response types
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*/
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static int get_cards_response(struct device_d *hw_dev, struct mci_cmd *cmd)
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{
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switch (cmd->resp_type) {
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case MMC_RSP_NONE:
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return 0;
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case MMC_RSP_R1:
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case MMC_RSP_R1b:
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case MMC_RSP_R3:
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cmd->response[0] = readl(hw_dev->map_base + HW_SSP_SDRESP0);
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return 1;
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case MMC_RSP_R2:
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cmd->response[3] = readl(hw_dev->map_base + HW_SSP_SDRESP0);
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cmd->response[2] = readl(hw_dev->map_base + HW_SSP_SDRESP1);
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cmd->response[1] = readl(hw_dev->map_base + HW_SSP_SDRESP2);
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cmd->response[0] = readl(hw_dev->map_base + HW_SSP_SDRESP3);
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return 4;
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}
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return -EINVAL;
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}
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/**
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* Finish a request to the MCI card
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* @param hw_dev Host interface device instance
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*
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* Can also stop the clock to save power
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*/
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static void finish_request(struct device_d *hw_dev)
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{
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/* stop the engines (normaly already done) */
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writel(SSP_CTRL0_RUN, hw_dev->map_base + HW_SSP_CTRL0 + 8);
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}
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/**
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* Check if the last command failed and if, why it failed
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* @param status HW_SSP_STATUS's content
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* @return 0 if no error, negative values else
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*/
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static int get_cmd_error(unsigned status)
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{
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if (status & SSP_STATUS_ERROR)
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pr_debug("Status Reg reports %08X\n", status);
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if (status & SSP_STATUS_TIMEOUT) {
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pr_debug("CMD timeout\n");
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return -ETIMEDOUT;
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} else if (status & SSP_STATUS_RESP_TIMEOUT) {
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pr_debug("RESP timeout\n");
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return -ETIMEDOUT;
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} else if (status & SSP_STATUS_RESP_CRC_ERR) {
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pr_debug("CMD crc error\n");
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return -EILSEQ;
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} else if (status & SSP_STATUS_RESP_ERR) {
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pr_debug("RESP error\n");
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return -EIO;
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}
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return 0;
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}
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/**
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* Define the timout for the next command
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* @param hw_dev Host interface device instance
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* @param to Timeout value in MCI card's bus clocks
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*/
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static void stm_setup_timout(struct device_d *hw_dev, unsigned to)
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{
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uint32_t reg;
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reg = readl(hw_dev->map_base + HW_SSP_TIMING) & ~SSP_TIMING_TIMEOUT_MASK;
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reg |= SSP_TIMING_TIMEOUT(to);
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writel(reg, hw_dev->map_base + HW_SSP_TIMING);
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}
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/**
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* Read data from the MCI card
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* @param hw_dev Host interface device instance
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* @param buffer To write data into
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* @param length Count of bytes to read (must be multiples of 4)
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* @return 0 on success, negative values else
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*
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* @note This routine uses PIO to read in the data bytes from the FIFO. This
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* may fail whith high clock speeds. If you receive -EIO errors you can try
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* again with reduced clock speeds.
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*/
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static int read_data(struct device_d *hw_dev, void *buffer, unsigned length)
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{
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uint32_t *p = buffer;
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if (length & 0x3) {
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pr_debug("Cannot read data sizes not multiple of 4 (request for %u detected)\n",
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length);
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return -EINVAL;
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}
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while ((length != 0) &&
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((readl(hw_dev->map_base + HW_SSP_STATUS) & SSP_STATUS_ERROR) == 0)) {
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/* TODO sort out FIFO overflows and emit -EOI for this case */
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if ((readl(hw_dev->map_base + HW_SSP_STATUS) & SSP_STATUS_FIFO_EMPTY) == 0) {
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*p = readl(hw_dev->map_base + HW_SSP_DATA);
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p++;
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length -= 4;
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}
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}
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if (length == 0)
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return 0;
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return -EINVAL;
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}
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/**
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* Write data into the MCI card
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* @param hw_dev Host interface device instance
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* @param buffer To read the data from
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* @param length Count of bytes to write (must be multiples of 4)
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* @return 0 on success, negative values else
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*
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* @note This routine uses PIO to write the data bytes into the FIFO. This
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* may fail with high clock speeds. If you receive -EIO errors you can try
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* again with reduced clock speeds.
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*/
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static int write_data(struct device_d *hw_dev, const void *buffer, unsigned length)
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{
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const uint32_t *p = buffer;
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if (length & 0x3) {
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pr_debug("Cannot write data sizes not multiple of 4 (request for %u detected)\n",
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length);
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return -EINVAL;
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}
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while ((length != 0) &&
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((readl(hw_dev->map_base + HW_SSP_STATUS) & SSP_STATUS_ERROR) == 0)) {
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/* TODO sort out FIFO overflows and emit -EOI for this case */
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if ((readl(hw_dev->map_base + HW_SSP_STATUS) & SSP_STATUS_FIFO_FULL) == 0) {
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writel(*p, hw_dev->map_base + HW_SSP_DATA);
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p++;
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length -= 4;
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}
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}
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if (length == 0)
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return 0;
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return -EINVAL;
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}
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/**
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* Start the transaction with or without data
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* @param hw_dev Host interface device instance
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* @param data Data transfer description (might be NULL)
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* @return 0 on success
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*/
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static int transfer_data(struct device_d *hw_dev, struct mci_data *data)
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{
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unsigned length;
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if (data != NULL) {
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length = data->blocks * data->blocksize;
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#if 0
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/*
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* For the records: When writing data with high clock speeds it
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* could be a good idea to fill the FIFO prior starting the
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* transaction.
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* But last time I tried it, it failed badly. Don't know why yet
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*/
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if (data->flags & MMC_DATA_WRITE) {
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err = write_data(host, data->src, 16);
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data->src += 16;
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length -= 16;
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}
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#endif
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}
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/*
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* Everything is ready for the transaction now:
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* - transfer configuration
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* - command and its parameters
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*
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* Start the transaction right now
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*/
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writel(SSP_CTRL0_RUN, hw_dev->map_base + HW_SSP_CTRL0 + 4);
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if (data != NULL) {
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if (data->flags & MMC_DATA_READ)
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return read_data(hw_dev, data->dest, length);
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else
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return write_data(hw_dev, data->src, length);
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}
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return 0;
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}
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/**
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* Configure the MCI hardware for the next transaction
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* @param cmd_flags Command information
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* @param data_flags Data information (may be 0)
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* @return Corresponding setting for the SSP_CTRL0 register
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*/
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static uint32_t prepare_transfer_setup(unsigned cmd_flags, unsigned data_flags)
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{
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uint32_t reg = 0;
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if (cmd_flags & MMC_RSP_PRESENT)
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reg |= SSP_CTRL0_GET_RESP;
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if ((cmd_flags & MMC_RSP_CRC) == 0)
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reg |= SSP_CTRL0_IGNORE_CRC;
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if (cmd_flags & MMC_RSP_136)
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reg |= SSP_CTRL0_LONG_RESP;
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if (cmd_flags & MMC_RSP_BUSY)
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reg |= SSP_CTRL0_WAIT_FOR_IRQ; /* FIXME correct? */
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#if 0
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if (cmd_flags & MMC_RSP_OPCODE)
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/* TODO */
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#endif
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if (data_flags & MMC_DATA_READ)
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reg |= SSP_CTRL0_READ;
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return reg;
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}
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/**
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* Handle MCI commands without data
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* @param hw_dev Host interface device instance
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* @param cmd The command to handle
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* @return 0 on success
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*
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* This functions handles the following MCI commands:
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* - "broadcast command (BC)" without a response
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* - "broadcast commands with response (BCR)"
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* - "addressed command (AC)" with response, but without data
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*/
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static int stm_mci_std_cmds(struct device_d *hw_dev, struct mci_cmd *cmd)
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{
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/* setup command and transfer parameters */
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writel(prepare_transfer_setup(cmd->resp_type, 0) |
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SSP_CTRL0_ENABLE, hw_dev->map_base + HW_SSP_CTRL0);
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/* prepare the command, when no response is expected add a few trailing clocks */
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writel(SSP_CMD0_CMD(cmd->cmdidx) |
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(cmd->resp_type & MMC_RSP_PRESENT ? 0 : SSP_CMD0_APPEND_8CYC),
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hw_dev->map_base + HW_SSP_CMD0);
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/* prepare command's arguments */
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writel(cmd->cmdarg, hw_dev->map_base + HW_SSP_CMD1);
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stm_setup_timout(hw_dev, 0xffff);
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/* start the transfer */
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writel(SSP_CTRL0_RUN, hw_dev->map_base + HW_SSP_CTRL0 + 4);
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/* wait until finished */
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while (readl(hw_dev->map_base + HW_SSP_CTRL0) & SSP_CTRL0_RUN)
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;
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if (cmd->resp_type & MMC_RSP_PRESENT)
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get_cards_response(hw_dev, cmd);
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return get_cmd_error(readl(hw_dev->map_base + HW_SSP_STATUS));
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}
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/**
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* Handle an "addressed data transfer command " with or without data
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* @param hw_dev Host interface device instance
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* @param cmd The command to handle
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* @param data The data information (buffer, direction aso.) May be NULL
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* @return 0 on success
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*/
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static int stm_mci_adtc(struct device_d *hw_dev, struct mci_cmd *cmd,
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struct mci_data *data)
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{
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struct stm_mci_host *host_data = (struct stm_mci_host*)GET_HOST_DATA(hw_dev);
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uint32_t xfer_cnt, log2blocksize, block_cnt;
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int err;
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/* Note: 'data' can be NULL! */
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if (data != NULL) {
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xfer_cnt = data->blocks * data->blocksize;
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block_cnt = data->blocks - 1; /* can be 0 */
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log2blocksize = find_first_bit((const unsigned long*)&data->blocksize,
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32);
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} else
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xfer_cnt = log2blocksize = block_cnt = 0;
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/* setup command and transfer parameters */
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writel(prepare_transfer_setup(cmd->resp_type, data != NULL ? data->flags : 0) |
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SSP_CTRL0_BUS_WIDTH(host_data->bus_width) |
|
||||
(xfer_cnt != 0 ? SSP_CTRL0_DATA_XFER : 0) | /* command plus data */
|
||||
SSP_CTRL0_ENABLE |
|
||||
SSP_CTRL0_XFER_COUNT(xfer_cnt), /* byte count to be transfered */
|
||||
hw_dev->map_base + HW_SSP_CTRL0);
|
||||
|
||||
/* prepare the command and the transfered data count */
|
||||
writel(SSP_CMD0_CMD(cmd->cmdidx) |
|
||||
SSP_CMD0_BLOCK_SIZE(log2blocksize) |
|
||||
SSP_CMD0_BLOCK_COUNT(block_cnt) |
|
||||
(cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION ? SSP_CMD0_APPEND_8CYC : 0),
|
||||
hw_dev->map_base + HW_SSP_CMD0);
|
||||
|
||||
/* prepare command's arguments */
|
||||
writel(cmd->cmdarg, hw_dev->map_base + HW_SSP_CMD1);
|
||||
|
||||
stm_setup_timout(hw_dev, 0xffff);
|
||||
|
||||
err = transfer_data(hw_dev, data);
|
||||
if (err != 0) {
|
||||
pr_debug(" Transfering data failed\n");
|
||||
return err;
|
||||
}
|
||||
|
||||
/* wait until finished */
|
||||
while (readl(hw_dev->map_base + HW_SSP_CTRL0) & SSP_CTRL0_RUN)
|
||||
;
|
||||
|
||||
get_cards_response(hw_dev, cmd);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* @param hw_dev Host interface device instance
|
||||
* @param nc New Clock in [Hz] (may be 0 to disable the clock)
|
||||
* @return The real clock frequency
|
||||
*
|
||||
* The SSP unit clock can base on the external 24 MHz or the internal 480 MHz
|
||||
* Its unit clock value is derived from the io clock, from the SSP divider
|
||||
* and at least the SSP bus clock itself is derived from the SSP unit's divider
|
||||
*
|
||||
* @code
|
||||
* |------------------- generic -------------|-peripheral specific-|-----all SSPs-----|-per SSP unit-|
|
||||
* 24 MHz ----------------------------
|
||||
* \ \
|
||||
* \ |----| FRAC |----IO CLK----| SSP unit DIV |---| SSP DIV |--- SSP output clock
|
||||
* \- | PLL |--- 480 MHz ---/
|
||||
* @endcode
|
||||
*
|
||||
* @note Up to "SSP unit DIV" the outer world must care. This routine only
|
||||
* handles the "SSP DIV".
|
||||
*/
|
||||
static unsigned setup_clock_speed(struct device_d *hw_dev, unsigned nc)
|
||||
{
|
||||
unsigned ssp, div1, div2, reg;
|
||||
|
||||
if (nc == 0U) {
|
||||
/* TODO stop the clock */
|
||||
return 0;
|
||||
}
|
||||
|
||||
ssp = imx_get_sspclk() * 1000;
|
||||
|
||||
for (div1 = 2; div1 < 255; div1 += 2) {
|
||||
div2 = ssp / nc / div1;
|
||||
if (div2 <= 0x100)
|
||||
break;
|
||||
}
|
||||
if (div1 >= 255) {
|
||||
pr_warning("Cannot set clock to %d Hz\n", nc);
|
||||
return 0;
|
||||
}
|
||||
|
||||
reg = readl(hw_dev->map_base + HW_SSP_TIMING) & SSP_TIMING_TIMEOUT_MASK;
|
||||
reg |= SSP_TIMING_CLOCK_DIVIDE(div1) | SSP_TIMING_CLOCK_RATE(div2 - 1);
|
||||
writel(reg, hw_dev->map_base + HW_SSP_TIMING);
|
||||
|
||||
return ssp / div1 / div2;
|
||||
}
|
||||
|
||||
/**
|
||||
* Reset the MCI engine (the hard way)
|
||||
* @param hw_dev Host interface instance
|
||||
*
|
||||
* This will reset everything in all registers of this unit! (FIXME)
|
||||
*/
|
||||
static void stm_mci_reset(struct device_d *hw_dev)
|
||||
{
|
||||
writel(SSP_CTRL0_SFTRST, hw_dev->map_base + HW_SSP_CTRL0 + 8);
|
||||
while (readl(hw_dev->map_base + HW_SSP_CTRL0) & SSP_CTRL0_SFTRST)
|
||||
;
|
||||
}
|
||||
|
||||
/**
|
||||
* Initialize the engine
|
||||
* @param hw_dev Host interface instance
|
||||
* @param mci_dev MCI device instance
|
||||
*/
|
||||
static int stm_mci_initialize(struct device_d *hw_dev, struct device_d *mci_dev)
|
||||
{
|
||||
struct mci_host *host = GET_MCI_PDATA(mci_dev);
|
||||
struct stm_mci_host *host_data = (struct stm_mci_host*)GET_HOST_DATA(hw_dev);
|
||||
|
||||
/* enable the clock to this unit to be able to reset it */
|
||||
writel(SSP_CTRL0_CLKGATE, hw_dev->map_base + HW_SSP_CTRL0 + 8);
|
||||
|
||||
/* reset the unit */
|
||||
stm_mci_reset(hw_dev);
|
||||
|
||||
/* restore the last settings */
|
||||
host->clock = host_data->clock = setup_clock_speed(hw_dev, host->clock);
|
||||
stm_setup_timout(hw_dev, 0xffff);
|
||||
writel(SSP_CTRL0_IGNORE_CRC |
|
||||
SSP_CTRL0_BUS_WIDTH(host_data->bus_width),
|
||||
hw_dev->map_base + HW_SSP_CTRL0);
|
||||
writel(SSP_CTRL1_POLARITY |
|
||||
SSP_CTRL1_SSP_MODE(3) |
|
||||
SSP_CTRL1_WORD_LENGTH(7), hw_dev->map_base + HW_SSP_CTRL1);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* ------------------------- MCI API -------------------------------------- */
|
||||
|
||||
/**
|
||||
* Keep the attached MMC/SD unit in a well know state
|
||||
* @param mci_pdata MCI platform data
|
||||
* @param mci_dev MCI device instance
|
||||
* @return 0 on success, negative value else
|
||||
*/
|
||||
static int mci_reset(struct mci_host *mci_pdata, struct device_d *mci_dev)
|
||||
{
|
||||
struct device_d *hw_dev = mci_pdata->hw_dev;
|
||||
|
||||
return stm_mci_initialize(hw_dev, mci_dev);
|
||||
}
|
||||
|
||||
/**
|
||||
* Process one command to the MCI card
|
||||
* @param mci_pdata MCI platform data
|
||||
* @param cmd The command to process
|
||||
* @param data The data to handle in the command (can be NULL)
|
||||
* @return 0 on success, negative value else
|
||||
*/
|
||||
static int mci_request(struct mci_host *mci_pdata, struct mci_cmd *cmd,
|
||||
struct mci_data *data)
|
||||
{
|
||||
struct device_d *hw_dev = mci_pdata->hw_dev;
|
||||
int rc;
|
||||
|
||||
if ((cmd->resp_type == 0) || (data == NULL))
|
||||
rc = stm_mci_std_cmds(hw_dev, cmd);
|
||||
else
|
||||
rc = stm_mci_adtc(hw_dev, cmd, data); /* with response and data */
|
||||
|
||||
finish_request(hw_dev); /* TODO */
|
||||
return rc;
|
||||
}
|
||||
|
||||
/**
|
||||
* Setup the bus width and IO speed
|
||||
* @param mci_pdata MCI platform data
|
||||
* @param mci_dev MCI device instance
|
||||
* @param bus_width New bus width value (1, 4 or 8)
|
||||
* @param clock New clock in Hz (can be '0' to disable the clock)
|
||||
*
|
||||
* Drivers currently realized values are stored in MCI's platformdata
|
||||
*/
|
||||
static void mci_set_ios(struct mci_host *mci_pdata, struct device_d *mci_dev,
|
||||
unsigned bus_width, unsigned clock)
|
||||
{
|
||||
struct device_d *hw_dev = mci_pdata->hw_dev;
|
||||
struct stm_mci_host *host_data = (struct stm_mci_host*)GET_HOST_DATA(hw_dev);
|
||||
struct mci_host *host = GET_MCI_PDATA(mci_dev);
|
||||
|
||||
switch (bus_width) {
|
||||
case 8:
|
||||
host_data->bus_width = 2;
|
||||
host->bus_width = 8; /* 8 bit is possible */
|
||||
break;
|
||||
case 4:
|
||||
host_data->bus_width = 1;
|
||||
host->bus_width = 4; /* 4 bit is possible */
|
||||
break;
|
||||
default:
|
||||
host_data->bus_width = 0;
|
||||
host->bus_width = 1; /* 1 bit is possible */
|
||||
break;
|
||||
}
|
||||
|
||||
host->clock = host_data->clock = setup_clock_speed(hw_dev, clock);
|
||||
pr_debug("IO settings: bus width=%d, frequency=%u Hz\n", host->bus_width,
|
||||
host->clock);
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------------- */
|
||||
|
||||
#ifdef CONFIG_MCI_INFO
|
||||
const unsigned char bus_width[3] = { 1, 4, 8 };
|
||||
|
||||
static void stm_info(struct device_d *hw_dev)
|
||||
{
|
||||
struct stm_mci_host *host_data = GET_HOST_DATA(hw_dev);
|
||||
|
||||
printf(" Interface\n");
|
||||
printf(" Min. bus clock: %u Hz\n", host_data->f_min);
|
||||
printf(" Max. bus clock: %u Hz\n", host_data->f_max);
|
||||
printf(" Current bus clock: %u Hz\n", host_data->clock);
|
||||
printf(" Bus width: %u bit\n", bus_width[host_data->bus_width]);
|
||||
printf("\n");
|
||||
}
|
||||
#endif
|
||||
|
||||
static int stm_mci_probe(struct device_d *hw_dev)
|
||||
{
|
||||
struct stm_mci_platform_data *pd = hw_dev->platform_data;
|
||||
struct stm_mci_host *host_data;
|
||||
struct mci_host *host;
|
||||
|
||||
if (hw_dev->platform_data == NULL) {
|
||||
pr_err("Missing platform data\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
host = xzalloc(sizeof(struct stm_mci_host) + sizeof(struct mci_host));
|
||||
host_data = (struct stm_mci_host*)&host[1];
|
||||
|
||||
hw_dev->priv = host_data;
|
||||
host->hw_dev = hw_dev;
|
||||
host->send_cmd = mci_request,
|
||||
host->set_ios = mci_set_ios,
|
||||
host->init = mci_reset,
|
||||
|
||||
/* feed forward the platform specific values */
|
||||
host->voltages = pd->voltages;
|
||||
host->host_caps = pd->caps;
|
||||
|
||||
if (pd->f_min == 0) {
|
||||
host->f_min = imx_get_sspclk() / 254U / 256U * 1000U;
|
||||
pr_debug("Min. frequency is %u Hz\n", host->f_min);
|
||||
} else {
|
||||
host->f_min = pd->f_min;
|
||||
pr_debug("Min. frequency is %u Hz, could be %u Hz\n",
|
||||
host->f_min, imx_get_sspclk() / 254U / 256U * 1000U);
|
||||
}
|
||||
if (pd->f_max == 0) {
|
||||
host->f_max = imx_get_sspclk() / 2U / 1U * 1000U;
|
||||
pr_debug("Max. frequency is %u Hz\n", host->f_max);
|
||||
} else {
|
||||
host->f_max = pd->f_max;
|
||||
pr_debug("Max. frequency is %u Hz, could be %u Hz\n",
|
||||
host->f_max, imx_get_sspclk() / 2U / 1U * 1000U);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_MCI_INFO
|
||||
host_data->f_min = host->f_min;
|
||||
host_data->f_max = host->f_max;
|
||||
#endif
|
||||
|
||||
return mci_register(host);
|
||||
}
|
||||
|
||||
static struct driver_d stm_mci_driver = {
|
||||
.name = "stm_mci",
|
||||
.probe = stm_mci_probe,
|
||||
#ifdef CONFIG_MCI_INFO
|
||||
.info = stm_info,
|
||||
#endif
|
||||
};
|
||||
|
||||
static int stm_mci_init_driver(void)
|
||||
{
|
||||
register_driver(&stm_mci_driver);
|
||||
return 0;
|
||||
}
|
||||
|
||||
device_initcall(stm_mci_init_driver);
|
Loading…
Reference in New Issue