[U-Boot] [PATCH 2/3] mmc: Add bcm2835 sdhost controller
Alexander Graf
agraf at suse.de
Tue Jan 16 13:46:37 UTC 2018
The BCM2835 family of SoCs has 2 different SD controllers: One based on
the SDHCI spec and a custom, home-grown one.
This patch implements a driver for the latter based on the Linux driver. This
is needed so that we can make use of device trees that assume driver presence
of both SD controllers.
Signed-off-by: Alexander Graf <agraf at suse.de>
---
drivers/mmc/Kconfig | 14 +
drivers/mmc/Makefile | 1 +
drivers/mmc/bcm2835_sdhost.c | 1000 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1015 insertions(+)
create mode 100644 drivers/mmc/bcm2835_sdhost.c
diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig
index ab0627a8af..9b90db908b 100644
--- a/drivers/mmc/Kconfig
+++ b/drivers/mmc/Kconfig
@@ -256,6 +256,20 @@ config MMC_UNIPHIER
This selects support for the Matsushita SD/MMC Host Controller on
SocioNext UniPhier and Renesas RCar SoCs.
+config MMC_BCM2835
+ bool "BCM2835 family custom SD/MMC Host Controller support"
+ depends on ARCH_BCM283X
+ depends on BLK && DM_MMC
+ depends on OF_CONTROL
+ default y
+ help
+ This selects support for the custom SD host controller in the BCM2835
+ family of devices.
+
+ If you have a BCM2835 platform with SD or MMC devices, say Y here.
+
+ If unsure, say N.
+
config MMC_SANDBOX
bool "Sandbox MMC support"
depends on SANDBOX
diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 64b6f21c61..42113e2603 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -64,3 +64,4 @@ obj-$(CONFIG_MMC_SDHCI_ZYNQ) += zynq_sdhci.o
obj-$(CONFIG_MMC_SUNXI) += sunxi_mmc.o
obj-$(CONFIG_MMC_UNIPHIER) += uniphier-sd.o
+obj-$(CONFIG_MMC_BCM2835) += bcm2835_sdhost.o
diff --git a/drivers/mmc/bcm2835_sdhost.c b/drivers/mmc/bcm2835_sdhost.c
new file mode 100644
index 0000000000..62fa68ae69
--- /dev/null
+++ b/drivers/mmc/bcm2835_sdhost.c
@@ -0,0 +1,1000 @@
+/*
+ * 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.
+ *
+ * This code was ported to U-Boot by
+ * Alexander Graf <agraf at suse.de>
+ * and is based on drivers/mmc/host/bcm2835.c in Linux which is written by
+ * Phil Elwell <phil at raspberrypi.org>
+ * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
+ * which is 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
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <common.h>
+#include <clk.h>
+#include <fdtdec.h>
+#include <mmc.h>
+#include <dm.h>
+#include <linux/compat.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/sizes.h>
+#include <power/regulator.h>
+#include <asm/unaligned.h>
+#include <mach/gpio.h>
+#include <asm/arch/msg.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define msleep(a) udelay(a * 1000)
+
+#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 /* SD card response (95:64) - 32 R */
+#define SDRSP3 0x1c /* SD card response (127:96) - 32 R */
+#define SDHSTS 0x20 /* SD host status - 11 R/W */
+#define SDVDD 0x30 /* SD card power control - 1 R/W */
+#define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */
+#define SDHCFG 0x38 /* Host configuration - 2 R/W */
+#define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */
+#define SDDATA 0x40 /* Data to/from SD card - 32 R/W */
+#define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */
+
+#define SDCMD_NEW_FLAG 0x8000
+#define SDCMD_FAIL_FLAG 0x4000
+#define SDCMD_BUSYWAIT 0x800
+#define SDCMD_NO_RESPONSE 0x400
+#define SDCMD_LONG_RESPONSE 0x200
+#define SDCMD_WRITE_CMD 0x80
+#define SDCMD_READ_CMD 0x40
+#define SDCMD_CMD_MASK 0x3f
+
+#define SDCDIV_MAX_CDIV 0x7ff
+
+#define SDHSTS_BUSY_IRPT 0x400
+#define SDHSTS_BLOCK_IRPT 0x200
+#define SDHSTS_SDIO_IRPT 0x100
+#define SDHSTS_REW_TIME_OUT 0x80
+#define SDHSTS_CMD_TIME_OUT 0x40
+#define SDHSTS_CRC16_ERROR 0x20
+#define SDHSTS_CRC7_ERROR 0x10
+#define SDHSTS_FIFO_ERROR 0x08
+/* Reserved */
+/* Reserved */
+#define SDHSTS_DATA_FLAG 0x01
+
+#define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \
+ SDHSTS_CRC16_ERROR | \
+ SDHSTS_REW_TIME_OUT | \
+ SDHSTS_FIFO_ERROR)
+
+#define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \
+ SDHSTS_TRANSFER_ERROR_MASK)
+
+#define SDHCFG_BUSY_IRPT_EN BIT(10)
+#define SDHCFG_BLOCK_IRPT_EN BIT(8)
+#define SDHCFG_SDIO_IRPT_EN BIT(5)
+#define SDHCFG_DATA_IRPT_EN BIT(4)
+#define SDHCFG_SLOW_CARD BIT(3)
+#define SDHCFG_WIDE_EXT_BUS BIT(2)
+#define SDHCFG_WIDE_INT_BUS BIT(1)
+#define SDHCFG_REL_CMD_LINE BIT(0)
+
+#define SDVDD_POWER_OFF 0
+#define SDVDD_POWER_ON 1
+
+#define SDEDM_FORCE_DATA_MODE BIT(19)
+#define SDEDM_CLOCK_PULSE BIT(20)
+#define SDEDM_BYPASS BIT(21)
+
+#define SDEDM_WRITE_THRESHOLD_SHIFT 9
+#define SDEDM_READ_THRESHOLD_SHIFT 14
+#define SDEDM_THRESHOLD_MASK 0x1f
+
+#define SDEDM_FSM_MASK 0xf
+#define SDEDM_FSM_IDENTMODE 0x0
+#define SDEDM_FSM_DATAMODE 0x1
+#define SDEDM_FSM_READDATA 0x2
+#define SDEDM_FSM_WRITEDATA 0x3
+#define SDEDM_FSM_READWAIT 0x4
+#define SDEDM_FSM_READCRC 0x5
+#define SDEDM_FSM_WRITECRC 0x6
+#define SDEDM_FSM_WRITEWAIT1 0x7
+#define SDEDM_FSM_POWERDOWN 0x8
+#define SDEDM_FSM_POWERUP 0x9
+#define SDEDM_FSM_WRITESTART1 0xa
+#define SDEDM_FSM_WRITESTART2 0xb
+#define SDEDM_FSM_GENPULSES 0xc
+#define SDEDM_FSM_WRITEWAIT2 0xd
+#define SDEDM_FSM_STARTPOWDOWN 0xf
+
+#define SDDATA_FIFO_WORDS 16
+
+#define FIFO_READ_THRESHOLD 4
+#define FIFO_WRITE_THRESHOLD 4
+#define SDDATA_FIFO_PIO_BURST 8
+
+struct bcm2835_plat {
+ struct mmc_config cfg;
+ struct mmc mmc;
+};
+
+struct bcm2835_host {
+ void __iomem *ioaddr;
+ u32 phys_addr;
+
+ int clock; /* Current clock speed */
+ unsigned int max_clk; /* Max possible freq */
+ unsigned int blocks; /* remaining PIO blocks */
+ int irq; /* Device IRQ */
+
+ u32 ns_per_fifo_word;
+
+ /* cached registers */
+ u32 hcfg;
+ u32 cdiv;
+
+ struct mmc_cmd *cmd; /* Current command */
+ struct mmc_data *data; /* Current data request */
+ bool data_complete:1;/* Data finished before cmd */
+ bool use_busy:1; /* Wait for busy interrupt */
+ bool wait_data_complete:1; /* Wait for data to complete */
+
+ /* for threaded irq handler */
+ bool irq_block;
+ bool irq_busy;
+ bool irq_data;
+
+ struct udevice *dev;
+ struct mmc *mmc;
+ struct bcm2835_plat *plat;
+};
+
+static void bcm2835_dumpregs(struct bcm2835_host *host)
+{
+ dev_dbg(dev, "=========== REGISTER DUMP ===========\n");
+ dev_dbg(dev, "SDCMD 0x%08x\n", readl(host->ioaddr + SDCMD));
+ dev_dbg(dev, "SDARG 0x%08x\n", readl(host->ioaddr + SDARG));
+ dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT));
+ dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV));
+ dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0));
+ dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1));
+ dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2));
+ dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3));
+ dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS));
+ dev_dbg(dev, "SDVDD 0x%08x\n", readl(host->ioaddr + SDVDD));
+ dev_dbg(dev, "SDEDM 0x%08x\n", readl(host->ioaddr + SDEDM));
+ dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG));
+ dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT));
+ dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC));
+ dev_dbg(dev, "===========================================\n");
+}
+
+static void bcm2835_reset_internal(struct bcm2835_host *host)
+{
+ u32 temp;
+
+ writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
+ writel(0, host->ioaddr + SDCMD);
+ writel(0, host->ioaddr + SDARG);
+ writel(0xf00000, host->ioaddr + SDTOUT);
+ writel(0, host->ioaddr + SDCDIV);
+ writel(0x7f8, host->ioaddr + SDHSTS); /* Write 1s to clear */
+ writel(0, host->ioaddr + SDHCFG);
+ writel(0, host->ioaddr + SDHBCT);
+ writel(0, host->ioaddr + SDHBLC);
+
+ /* Limit fifo usage due to silicon bug */
+ temp = readl(host->ioaddr + SDEDM);
+ temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |
+ (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));
+ temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
+ (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
+ writel(temp, host->ioaddr + SDEDM);
+ msleep(20);
+ writel(SDVDD_POWER_ON, host->ioaddr + SDVDD);
+ msleep(20);
+ host->clock = 0;
+ writel(host->hcfg, host->ioaddr + SDHCFG);
+ writel(host->cdiv, host->ioaddr + SDCDIV);
+}
+
+static int bcm2835_finish_command(struct bcm2835_host *host);
+
+static void bcm2835_wait_transfer_complete(struct bcm2835_host *host)
+{
+ int timediff;
+ u32 alternate_idle;
+
+ alternate_idle = (host->data->flags & MMC_DATA_READ) ?
+ SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1;
+
+ timediff = 0;
+
+ while (1) {
+ u32 edm, fsm;
+
+ edm = readl(host->ioaddr + SDEDM);
+ fsm = edm & SDEDM_FSM_MASK;
+
+ if ((fsm == SDEDM_FSM_IDENTMODE) ||
+ (fsm == SDEDM_FSM_DATAMODE))
+ break;
+ if (fsm == alternate_idle) {
+ writel(edm | SDEDM_FORCE_DATA_MODE,
+ host->ioaddr + SDEDM);
+ break;
+ }
+
+ timediff++;
+ if (timediff == 100000) {
+ dev_err(host->dev,
+ "wait_transfer_complete - still waiting after %d retries\n",
+ timediff);
+ bcm2835_dumpregs(host);
+ return;
+ }
+ }
+}
+
+static int bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read)
+{
+ size_t blksize;
+
+ blksize = host->data->blocksize;
+
+ while (blksize) {
+ int copy_words;
+ u32 hsts = 0;
+ size_t len;
+ u32 *buf;
+
+ len = blksize;
+ if (len % 4)
+ return -EINVAL;
+
+ blksize -= len;
+
+ buf = is_read ? (u32 *)host->data->dest : (u32 *)host->data->src;
+
+ if (is_read)
+ host->data->dest += len;
+ else
+ host->data->src += len;
+
+ copy_words = len / 4;
+
+ while (copy_words) {
+ int burst_words, words;
+ u32 edm;
+
+ burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words);
+ edm = readl(host->ioaddr + SDEDM);
+ if (is_read)
+ words = ((edm >> 4) & 0x1f);
+ else
+ words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f);
+
+ if (words < burst_words) {
+ int fsm_state = (edm & SDEDM_FSM_MASK);
+
+ if ((is_read &&
+ (fsm_state != SDEDM_FSM_READDATA &&
+ fsm_state != SDEDM_FSM_READWAIT &&
+ fsm_state != SDEDM_FSM_READCRC)) ||
+ (!is_read &&
+ (fsm_state != SDEDM_FSM_WRITEDATA &&
+ fsm_state != SDEDM_FSM_WRITESTART1 &&
+ fsm_state != SDEDM_FSM_WRITESTART2))) {
+ hsts = readl(host->ioaddr + SDHSTS);
+ printf("fsm %x, hsts %08x\n",
+ fsm_state, hsts);
+ if (hsts & SDHSTS_ERROR_MASK)
+ break;
+ }
+
+ continue;
+ } else if (words > copy_words) {
+ words = copy_words;
+ }
+
+ copy_words -= words;
+
+ while (words) {
+ if (is_read)
+ *(buf++) = readl(host->ioaddr + SDDATA);
+ else
+ writel(*(buf++), host->ioaddr + SDDATA);
+ words--;
+ }
+ }
+
+ if (hsts & SDHSTS_ERROR_MASK)
+ break;
+ }
+
+ return 0;
+}
+
+static int bcm2835_transfer_pio(struct bcm2835_host *host)
+{
+ u32 sdhsts;
+ bool is_read;
+ int r = 0;
+
+ is_read = (host->data->flags & MMC_DATA_READ) != 0;
+ r = bcm2835_transfer_block_pio(host, is_read);
+
+ if (host->wait_data_complete)
+ bcm2835_wait_transfer_complete(host);
+
+ sdhsts = readl(host->ioaddr + SDHSTS);
+ if (sdhsts & (SDHSTS_CRC16_ERROR |
+ SDHSTS_CRC7_ERROR |
+ SDHSTS_FIFO_ERROR)) {
+ printf("%s transfer error - HSTS %08x\n",
+ is_read ? "read" : "write", sdhsts);
+ r = -EILSEQ;
+ } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
+ SDHSTS_REW_TIME_OUT))) {
+ printf("%s timeout error - HSTS %08x\n",
+ is_read ? "read" : "write", sdhsts);
+ r = -ETIMEDOUT;
+ }
+
+ return r;
+}
+
+static void bcm2835_set_transfer_irqs(struct bcm2835_host *host)
+{
+ u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN |
+ SDHCFG_BUSY_IRPT_EN;
+
+ host->hcfg = (host->hcfg & ~all_irqs) |
+ SDHCFG_DATA_IRPT_EN |
+ SDHCFG_BUSY_IRPT_EN;
+
+ writel(host->hcfg, host->ioaddr + SDHCFG);
+}
+
+static
+void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_cmd *cmd,
+ struct mmc_data *data)
+{
+ WARN_ON(host->data);
+
+ host->data = data;
+ if (!data)
+ return;
+
+ host->wait_data_complete = cmd->cmdidx != MMC_CMD_READ_MULTIPLE_BLOCK;
+ host->data_complete = false;
+
+ /* Use PIO */
+ host->blocks = data->blocks;
+
+ bcm2835_set_transfer_irqs(host);
+
+ writel(data->blocksize, host->ioaddr + SDHBCT);
+ writel(data->blocks, host->ioaddr + SDHBLC);
+}
+
+static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms)
+{
+ u32 value;
+ int ret;
+ int timeout_us = (max_ms * 1000);
+
+ ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
+ !(value & SDCMD_NEW_FLAG), 10);
+ if (ret == -ETIMEDOUT)
+ /* if it takes a while make poll interval bigger */
+ ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
+ !(value & SDCMD_NEW_FLAG),
+ timeout_us);
+ if (ret == -ETIMEDOUT)
+ printf("%s: timeout (%d ms)\n", __func__, max_ms);
+
+ return value;
+}
+
+static int bcm2835_send_command(struct bcm2835_host *host, struct mmc_cmd *cmd,
+ struct mmc_data *data)
+{
+ u32 sdcmd, sdhsts;
+
+ WARN_ON(host->cmd);
+
+ sdcmd = bcm2835_read_wait_sdcmd(host, 100);
+ if (sdcmd & SDCMD_NEW_FLAG) {
+ printf("previous command never completed.\n");
+ bcm2835_dumpregs(host);
+ return -EILSEQ;
+ }
+
+ host->cmd = cmd;
+
+ /* Clear any error flags */
+ sdhsts = readl(host->ioaddr + SDHSTS);
+ if (sdhsts & SDHSTS_ERROR_MASK)
+ writel(sdhsts, host->ioaddr + SDHSTS);
+
+ if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY)) {
+ printf("unsupported response type!\n");
+ return -EINVAL;
+ }
+
+ bcm2835_prepare_data(host, cmd, data);
+
+ writel(cmd->cmdarg, host->ioaddr + SDARG);
+
+ sdcmd = cmd->cmdidx & SDCMD_CMD_MASK;
+
+ host->use_busy = false;
+ if (!(cmd->resp_type & MMC_RSP_PRESENT)) {
+ sdcmd |= SDCMD_NO_RESPONSE;
+ } else {
+ if (cmd->resp_type & MMC_RSP_136)
+ sdcmd |= SDCMD_LONG_RESPONSE;
+ if (cmd->resp_type & MMC_RSP_BUSY) {
+ sdcmd |= SDCMD_BUSYWAIT;
+ host->use_busy = true;
+ }
+ }
+
+ if (data) {
+ if (data->flags & MMC_DATA_WRITE)
+ sdcmd |= SDCMD_WRITE_CMD;
+ if (data->flags & MMC_DATA_READ)
+ sdcmd |= SDCMD_READ_CMD;
+ }
+
+ writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD);
+
+ return 0;
+}
+
+static int bcm2835_transfer_complete(struct bcm2835_host *host)
+{
+ int r = 0;
+
+ WARN_ON(!host->data_complete);
+
+ host->data = NULL;
+
+ return r;
+}
+
+static void bcm2835_finish_data(struct bcm2835_host *host)
+{
+ host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
+ writel(host->hcfg, host->ioaddr + SDHCFG);
+
+ host->data_complete = true;
+
+ if (host->cmd) {
+ /* Data managed to finish before the
+ * command completed. Make sure we do
+ * things in the proper order.
+ */
+ dev_dbg(dev, "Finished early - HSTS %08x\n",
+ readl(host->ioaddr + SDHSTS));
+ } else {
+ bcm2835_transfer_complete(host);
+ }
+}
+
+static int bcm2835_finish_command(struct bcm2835_host *host)
+{
+ struct mmc_cmd *cmd = host->cmd;
+ u32 sdcmd;
+ int r = 0;
+
+ sdcmd = bcm2835_read_wait_sdcmd(host, 100);
+
+ /* Check for errors */
+ if (sdcmd & SDCMD_NEW_FLAG) {
+ printf("command never completed.\n");
+ bcm2835_dumpregs(host);
+ return -EIO;
+ } else if (sdcmd & SDCMD_FAIL_FLAG) {
+ u32 sdhsts = readl(host->ioaddr + SDHSTS);
+
+ /* Clear the errors */
+ writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS);
+
+ if (!(sdhsts & SDHSTS_CRC7_ERROR) ||
+ (host->cmd->cmdidx != MMC_CMD_SEND_OP_COND)) {
+ if (sdhsts & SDHSTS_CMD_TIME_OUT) {
+ return -ETIMEDOUT;
+ } else {
+ printf("unexpected command %d error\n",
+ host->cmd->cmdidx);
+ bcm2835_dumpregs(host);
+ return -EILSEQ;
+ }
+ }
+ }
+
+ if (cmd->resp_type & MMC_RSP_PRESENT) {
+ if (cmd->resp_type & MMC_RSP_136) {
+ int i;
+
+ for (i = 0; i < 4; i++) {
+ cmd->response[3 - i] =
+ readl(host->ioaddr + SDRSP0 + i * 4);
+ }
+ } else {
+ cmd->response[0] = readl(host->ioaddr + SDRSP0);
+ }
+ }
+
+ /* Processed actual command. */
+ host->cmd = NULL;
+ if (host->data && host->data_complete)
+ r = bcm2835_transfer_complete(host);
+
+ return r;
+}
+
+static int bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)
+{
+ int r = -EINVAL;
+
+ if (!(intmask & SDHSTS_ERROR_MASK))
+ return 0;
+
+ if (!host->cmd)
+ return -EINVAL;
+
+ printf("sdhost_busy_irq: intmask %08x\n", intmask);
+ if (intmask & SDHSTS_CRC7_ERROR) {
+ r = -EILSEQ;
+ } else if (intmask & (SDHSTS_CRC16_ERROR |
+ SDHSTS_FIFO_ERROR)) {
+ r = -EILSEQ;
+ } else if (intmask & SDHSTS_REW_TIME_OUT) {
+ r = -ETIMEDOUT;
+ } else if (intmask & SDHSTS_CMD_TIME_OUT) {
+ r = -ETIMEDOUT;
+ }
+ bcm2835_dumpregs(host);
+ return r;
+}
+
+static int bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)
+{
+ int r = 0;
+
+ if (!host->data)
+ return 0;
+ if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))
+ r = -EILSEQ;
+ if (intmask & SDHSTS_REW_TIME_OUT)
+ r = -ETIMEDOUT;
+
+ if (r)
+ printf("%s:%d %d\n", __func__, __LINE__, r);
+
+ return r;
+}
+
+static void bcm2835_busy_irq(struct bcm2835_host *host)
+{
+ if (WARN_ON(!host->cmd)) {
+ bcm2835_dumpregs(host);
+ return;
+ }
+
+ if (WARN_ON(!host->use_busy)) {
+ bcm2835_dumpregs(host);
+ return;
+ }
+ host->use_busy = false;
+
+ bcm2835_finish_command(host);
+}
+
+static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask)
+{
+ int r;
+
+ /* There are no dedicated data/space available interrupt
+ * status bits, so it is necessary to use the single shared
+ * data/space available FIFO status bits. It is therefore not
+ * an error to get here when there is no data transfer in
+ * progress.
+ */
+ if (!host->data)
+ return;
+
+ r = bcm2835_check_data_error(host, intmask);
+ if (r)
+ goto finished;
+
+ if (host->data->flags & MMC_DATA_WRITE) {
+ /* Use the block interrupt for writes after the first block */
+ host->hcfg &= ~(SDHCFG_DATA_IRPT_EN);
+ host->hcfg |= SDHCFG_BLOCK_IRPT_EN;
+ writel(host->hcfg, host->ioaddr + SDHCFG);
+ bcm2835_transfer_pio(host);
+ } else {
+ bcm2835_transfer_pio(host);
+ host->blocks--;
+ if ((host->blocks == 0))
+ goto finished;
+ }
+ return;
+
+finished:
+ host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
+ writel(host->hcfg, host->ioaddr + SDHCFG);
+}
+
+static void bcm2835_data_threaded_irq(struct bcm2835_host *host)
+{
+ if (!host->data)
+ return;
+ if ((host->blocks == 0))
+ bcm2835_finish_data(host);
+}
+
+static void bcm2835_block_irq(struct bcm2835_host *host)
+{
+ if (WARN_ON(!host->data)) {
+ bcm2835_dumpregs(host);
+ return;
+ }
+
+ WARN_ON(!host->blocks);
+ if ((--host->blocks == 0))
+ bcm2835_finish_data(host);
+ else
+ bcm2835_transfer_pio(host);
+}
+
+static irqreturn_t bcm2835_irq(int irq, void *dev_id)
+{
+ irqreturn_t result = IRQ_NONE;
+ struct bcm2835_host *host = dev_id;
+ u32 intmask;
+
+ intmask = readl(host->ioaddr + SDHSTS);
+
+ writel(SDHSTS_BUSY_IRPT |
+ SDHSTS_BLOCK_IRPT |
+ SDHSTS_SDIO_IRPT |
+ SDHSTS_DATA_FLAG,
+ host->ioaddr + SDHSTS);
+
+ if (intmask & SDHSTS_BLOCK_IRPT) {
+ bcm2835_check_data_error(host, intmask);
+ host->irq_block = true;
+ result = IRQ_WAKE_THREAD;
+ }
+
+ if (intmask & SDHSTS_BUSY_IRPT) {
+ if (!bcm2835_check_cmd_error(host, intmask)) {
+ host->irq_busy = true;
+ result = IRQ_WAKE_THREAD;
+ } else {
+ result = IRQ_HANDLED;
+ }
+ }
+
+ /* There is no true data interrupt status bit, so it is
+ * necessary to qualify the data flag with the interrupt
+ * enable bit.
+ */
+ if ((intmask & SDHSTS_DATA_FLAG) &&
+ (host->hcfg & SDHCFG_DATA_IRPT_EN)) {
+ bcm2835_data_irq(host, intmask);
+ host->irq_data = true;
+ result = IRQ_WAKE_THREAD;
+ }
+
+ return result;
+}
+
+static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id)
+{
+ struct bcm2835_host *host = dev_id;
+ bool block, busy, data;
+
+ block = host->irq_block;
+ busy = host->irq_busy;
+ data = host->irq_data;
+ host->irq_block = false;
+ host->irq_busy = false;
+ host->irq_data = false;
+
+ if (block)
+ bcm2835_block_irq(host);
+ if (busy)
+ bcm2835_busy_irq(host);
+ if (data)
+ bcm2835_data_threaded_irq(host);
+
+ return IRQ_HANDLED;
+}
+
+static void bcm2835_irq_poll(struct bcm2835_host *host)
+{
+ u32 intmask;
+
+ while (1) {
+ intmask = readl(host->ioaddr + SDHSTS);
+ if (intmask & (SDHSTS_BUSY_IRPT | SDHSTS_BLOCK_IRPT |
+ SDHSTS_SDIO_IRPT | SDHSTS_DATA_FLAG)) {
+ bcm2835_irq(0, host);
+ bcm2835_threaded_irq(0, host);
+ return;
+ }
+ }
+}
+
+static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)
+{
+ int div;
+
+ /* The SDCDIV register has 11 bits, and holds (div - 2). But
+ * in data mode the max is 50MHz wihout a minimum, and only
+ * the bottom 3 bits are used. Since the switch over is
+ * automatic (unless we have marked the card as slow...),
+ * chosen values have to make sense in both modes. Ident mode
+ * must be 100-400KHz, so can range check the requested
+ * clock. CMD15 must be used to return to data mode, so this
+ * can be monitored.
+ *
+ * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz
+ * 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz
+ *
+ * 623->400KHz/27.8MHz
+ * reset value (507)->491159/50MHz
+ *
+ * BUT, the 3-bit clock divisor in data mode is too small if
+ * the core clock is higher than 250MHz, so instead use the
+ * SLOW_CARD configuration bit to force the use of the ident
+ * clock divisor at all times.
+ */
+
+ if (clock < 100000) {
+ /* Can't stop the clock, but make it as slow as possible
+ * to show willing
+ */
+ host->cdiv = SDCDIV_MAX_CDIV;
+ writel(host->cdiv, host->ioaddr + SDCDIV);
+ return;
+ }
+
+ div = host->max_clk / clock;
+ if (div < 2)
+ div = 2;
+ if ((host->max_clk / div) > clock)
+ div++;
+ div -= 2;
+
+ if (div > SDCDIV_MAX_CDIV)
+ div = SDCDIV_MAX_CDIV;
+
+ clock = host->max_clk / (div + 2);
+ host->mmc->clock = clock;
+
+ /* Calibrate some delays */
+
+ host->ns_per_fifo_word = (1000000000 / clock) *
+ ((host->mmc->card_caps & MMC_MODE_4BIT) ? 8 : 32);
+
+ host->cdiv = div;
+ writel(host->cdiv, host->ioaddr + SDCDIV);
+
+ /* Set the timeout to 500ms */
+ writel(host->mmc->clock / 2, host->ioaddr + SDTOUT);
+}
+
+static inline int is_power_of_2(u64 x)
+{
+ return !(x & (x - 1));
+}
+
+static int bcm2835_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
+ struct mmc_data *data)
+{
+ struct bcm2835_host *host = dev_get_priv(dev);
+ u32 edm, fsm;
+ int r = 0;
+
+ if (data && !is_power_of_2(data->blocksize)) {
+ printf("unsupported block size (%d bytes)\n",
+ data->blocksize);
+
+ if (cmd)
+ return -EINVAL;
+ }
+
+ edm = readl(host->ioaddr + SDEDM);
+ fsm = edm & SDEDM_FSM_MASK;
+
+ if ((fsm != SDEDM_FSM_IDENTMODE) &&
+ (fsm != SDEDM_FSM_DATAMODE) &&
+ (cmd && cmd->cmdidx != MMC_CMD_STOP_TRANSMISSION)) {
+ printf("previous command (%d) not complete (EDM %08x)\n",
+ readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK,
+ edm);
+ bcm2835_dumpregs(host);
+
+ if (cmd)
+ return -EILSEQ;
+
+ return 0;
+ }
+
+ if (cmd && !(r = bcm2835_send_command(host, cmd, data)))
+ if (!host->use_busy)
+ r = bcm2835_finish_command(host);
+
+ /* Wait for completion of busy signal or data transfer */
+ while (host->use_busy || host->data)
+ bcm2835_irq_poll(host);
+
+ return r;
+}
+
+static int bcm2835_set_ios(struct udevice *dev)
+{
+ struct bcm2835_host *host = dev_get_priv(dev);
+ struct mmc *mmc = mmc_get_mmc_dev(dev);
+
+ if (!mmc->clock || mmc->clock != host->clock) {
+ bcm2835_set_clock(host, mmc->clock);
+ host->clock = mmc->clock;
+ }
+
+ /* set bus width */
+ host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;
+ if (mmc->bus_width == 4)
+ host->hcfg |= SDHCFG_WIDE_EXT_BUS;
+
+ host->hcfg |= SDHCFG_WIDE_INT_BUS;
+
+ /* Disable clever clock switching, to cope with fast core clocks */
+ host->hcfg |= SDHCFG_SLOW_CARD;
+
+ writel(host->hcfg, host->ioaddr + SDHCFG);
+
+ return 0;
+}
+
+static int bcm2835_add_host(struct bcm2835_host *host)
+{
+ struct mmc_config *cfg = &host->plat->cfg;
+
+ cfg->f_max = host->max_clk;
+ cfg->f_min = host->max_clk / SDCDIV_MAX_CDIV;
+ cfg->b_max = 65535;
+
+ dev_dbg(dev, "f_max %d, f_min %d\n",
+ cfg->f_max, cfg->f_min);
+
+ /* host controller capabilities */
+ cfg->host_caps = MMC_MODE_4BIT | MMC_MODE_HS | MMC_MODE_HS_52MHz;
+
+ /* report supported voltage ranges */
+ cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
+
+ /* Set interrupt enables */
+ host->hcfg = SDHCFG_BUSY_IRPT_EN;
+
+ bcm2835_reset_internal(host);
+
+ return 0;
+}
+
+static int bcm2835_probe(struct udevice *dev)
+{
+ struct bcm2835_plat *plat = dev_get_platdata(dev);
+ struct bcm2835_host *host = dev_get_priv(dev);
+ struct mmc *mmc = mmc_get_mmc_dev(dev);
+ struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
+ int ret;
+ int pinctrl_handle;
+
+ host->dev = dev;
+ host->mmc = mmc;
+ host->plat = plat;
+ upriv->mmc = &plat->mmc;
+ plat->cfg.name = dev->name;
+
+ host->phys_addr = devfdt_get_addr(dev);
+ if (host->phys_addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ host->ioaddr = devm_ioremap(dev, host->phys_addr, SZ_256);
+ if (!host->ioaddr)
+ return -ENOMEM;
+
+ host->max_clk = bcm2835_get_mmc_clock();
+
+ pinctrl_handle = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), "pinctrl-0", -1);
+ if (pinctrl_handle != -1) {
+ struct udevice *dev;
+
+ /* Need to set up pinmuxing */
+ if (!uclass_first_device(UCLASS_GPIO, &dev) && dev)
+ bcm2835_gpio_set_pinmux(dev, pinctrl_handle);
+ }
+
+ ret = bcm2835_add_host(host);
+ if (ret)
+ goto err;
+
+ dev_dbg(dev, "%s -> OK\n", __func__);
+
+ return 0;
+
+err:
+ dev_dbg(dev, "%s -> err %d\n", __func__, ret);
+
+ return ret;
+}
+
+static const struct udevice_id bcm2835_match[] = {
+ { .compatible = "brcm,bcm2835-sdhost" },
+ { }
+};
+
+static const struct dm_mmc_ops bcm2835_ops = {
+ .send_cmd = bcm2835_send_cmd,
+ .set_ios = bcm2835_set_ios,
+};
+
+static int bcm2835_bind(struct udevice *dev)
+{
+ struct bcm2835_plat *plat = dev_get_platdata(dev);
+ return mmc_bind(dev, &plat->mmc, &plat->cfg);
+}
+
+U_BOOT_DRIVER(bcm2835_sdhost) = {
+ .name = "bcm2835-sdhost",
+ .id = UCLASS_MMC,
+ .of_match = bcm2835_match,
+ .bind = bcm2835_bind,
+ .probe = bcm2835_probe,
+ .priv_auto_alloc_size = sizeof(struct bcm2835_host),
+ .platdata_auto_alloc_size = sizeof(struct bcm2835_plat),
+ .ops = &bcm2835_ops,
+};
--
2.12.3
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