[RFC PATCH v2 3/4] sdhci-of: reorganize driver to support additional hardware

Albert Herranz
2009-12-14T22:24:32Z

This patch breaks down sdhci-of into a core portion and a eSDHC portion,
clearing the path to easily support additional hardware using the same
OF driver.

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
---
drivers/mmc/host/Kconfig | 26 ++++++-
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-of-core.c | 140 ++++--------------------------------
drivers/mmc/host/sdhci-of-esdhc.c | 143 +++++++++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci-of.h | 41 +++++++++++
5 files changed, 224 insertions(+), 127 deletions(-)
create mode 100644 drivers/mmc/host/sdhci-of-esdhc.c
create mode 100644 drivers/mmc/host/sdhci-of.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 432ae83..92076b3 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -44,6 +44,19 @@ config MMC_SDHCI_IO_ACCESSORS
This is silent Kconfig symbol that is selected by the drivers that
need to overwrite SDHCI IO memory accessors.

+config MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
+ bool
+ select MMC_SDHCI_IO_ACCESSORS
+ help
+ This option is selected by drivers running on big endian hosts
+ and performing I/O to a SDHCI controller through a bus that
+ implements a hardware byte swapper using a 32-bit datum.
+ This endian mapping mode is called "data invariance" and
+ has the effect of scrambling the addresses and formats of data
+ accessed in sizes other than the datum size.
+
+ This is the case for the Freescale eSDHC.
+
config MMC_SDHCI_PCI
tristate "SDHCI support on PCI bus"
depends on MMC_SDHCI && PCI
@@ -75,11 +88,18 @@ config MMC_RICOH_MMC
config MMC_SDHCI_OF
tristate "SDHCI support on OpenFirmware platforms"
depends on MMC_SDHCI && PPC_OF
- select MMC_SDHCI_IO_ACCESSORS
help
This selects the OF support for Secure Digital Host Controller
- Interfaces. So far, only the Freescale eSDHC controller is known
- to exist on OF platforms.
+ Interfaces.
+
+ If unsure, say N.
+
+config MMC_SDHCI_OF_ESDHC
+ bool "SDHCI OF support for the Freescale eSDHC controller"
+ depends on MMC_SDHCI_OF
+ select MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
+ help
+ This selects the Freescale eSDHC controller support.

If unsure, say N.

diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index b35a8e5..2563c81 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_MMC_VIA_SDMMC) += via-sdmmc.o

obj-$(CONFIG_MMC_SDHCI_OF) += sdhci-of.o
sdhci-of-y := sdhci-of-core.o
+sdhci-of-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o

ifeq ($(CONFIG_CB710_DEBUG),y)
CFLAGS-cb710-mmc += -DDEBUG
diff --git a/drivers/mmc/host/sdhci-of-core.c b/drivers/mmc/host/sdhci-of-core.c
index 01ab916..add2008 100644
--- a/drivers/mmc/host/sdhci-of-core.c
+++ b/drivers/mmc/host/sdhci-of-core.c
@@ -22,62 +22,37 @@
#include <linux/of_platform.h>
#include <linux/mmc/host.h>
#include <asm/machdep.h>
+#include "sdhci-of.h"
#include "sdhci.h"

-struct sdhci_of_data {
- unsigned int quirks;
- struct sdhci_ops ops;
-};
-
-struct sdhci_of_host {
- unsigned int clock;
- u16 xfer_mode_shadow;
-};
+#ifdef CONFIG_MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER

/*
- * Ops and quirks for the Freescale eSDHC controller.
+ * These accessors are designed for big endian hosts doing I/O to
+ * little endian controllers incorporating a 32-bit hardware byte swapper.
*/

-#define ESDHC_DMA_SYSCTL 0x40c
-#define ESDHC_DMA_SNOOP 0x00000040
-
-#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
-
-#define ESDHC_HOST_CONTROL_RES 0x05
-
-static u32 esdhc_readl(struct sdhci_host *host, int reg)
+u32 sdhci_be32bs_readl(struct sdhci_host *host, int reg)
{
return in_be32(host->ioaddr + reg);
}

-static u16 esdhc_readw(struct sdhci_host *host, int reg)
+u16 sdhci_be32bs_readw(struct sdhci_host *host, int reg)
{
- u16 ret;
-
- if (unlikely(reg == SDHCI_HOST_VERSION))
- ret = in_be16(host->ioaddr + reg);
- else
- ret = in_be16(host->ioaddr + (reg ^ 0x2));
- return ret;
+ return in_be16(host->ioaddr + (reg ^ 0x2));
}

-static u8 esdhc_readb(struct sdhci_host *host, int reg)
+u8 sdhci_be32bs_readb(struct sdhci_host *host, int reg)
{
return in_8(host->ioaddr + (reg ^ 0x3));
}

-static void esdhc_writel(struct sdhci_host *host, u32 val, int reg)
+void sdhci_be32bs_writel(struct sdhci_host *host, u32 val, int reg)
{
out_be32(host->ioaddr + reg, val);
}

-static void esdhc_writew(struct sdhci_host *host, u16 val, int reg)
+void sdhci_be32bs_writew(struct sdhci_host *host, u16 val, int reg)
{
struct sdhci_of_host *of_host = sdhci_priv(host);
int base = reg & ~0x3;
@@ -92,106 +67,21 @@ static void esdhc_writew(struct sdhci_host *host, u16 val, int reg)
of_host->xfer_mode_shadow = val;
return;
case SDHCI_COMMAND:
- esdhc_writel(host, val << 16 | of_host->xfer_mode_shadow,
- SDHCI_TRANSFER_MODE);
+ sdhci_be32bs_writel(host, val << 16 | of_host->xfer_mode_shadow,
+ SDHCI_TRANSFER_MODE);
return;
- case SDHCI_BLOCK_SIZE:
- /*
- * Two last DMA bits are reserved, and first one is used for
- * non-standard blksz of 4096 bytes that we don't support
- * yet. So clear the DMA boundary bits.
- */
- val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
- /* fall through */
}
clrsetbits_be32(host->ioaddr + base, 0xffff << shift, val << shift);
}

-static void esdhc_writeb(struct sdhci_host *host, u8 val, int reg)
+void sdhci_be32bs_writeb(struct sdhci_host *host, u8 val, int reg)
{
int base = reg & ~0x3;
int shift = (reg & 0x3) * 8;

- /* Prevent SDHCI core from writing reserved bits (e.g. HISPD). */
- if (reg == SDHCI_HOST_CONTROL)
- val &= ~ESDHC_HOST_CONTROL_RES;
-
clrsetbits_be32(host->ioaddr + base , 0xff << shift, val << shift);
}
-
-static void esdhc_set_clock(struct sdhci_host *host, unsigned int clock)
-{
- int pre_div = 2;
- int div = 1;
-
- clrbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
- ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN | ESDHC_CLOCK_MASK);
-
- 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--;
-
- setbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
- ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN |
- div << ESDHC_DIVIDER_SHIFT | pre_div << ESDHC_PREDIV_SHIFT);
- mdelay(100);
-out:
- host->clock = clock;
-}
-
-static int esdhc_enable_dma(struct sdhci_host *host)
-{
- setbits32(host->ioaddr + ESDHC_DMA_SYSCTL, ESDHC_DMA_SNOOP);
- return 0;
-}
-
-static unsigned int esdhc_get_max_clock(struct sdhci_host *host)
-{
- struct sdhci_of_host *of_host = sdhci_priv(host);
-
- return of_host->clock;
-}
-
-static unsigned int esdhc_get_min_clock(struct sdhci_host *host)
-{
- struct sdhci_of_host *of_host = sdhci_priv(host);
-
- return of_host->clock / 256 / 16;
-}
-
-static struct sdhci_of_data sdhci_esdhc = {
- .quirks = SDHCI_QUIRK_FORCE_BLK_SZ_2048 |
- SDHCI_QUIRK_BROKEN_CARD_DETECTION |
- 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 |
- SDHCI_QUIRK_NO_CARD_NO_RESET,
- .ops = {
- .readl = esdhc_readl,
- .readw = esdhc_readw,
- .readb = esdhc_readb,
- .writel = esdhc_writel,
- .writew = esdhc_writew,
- .writeb = esdhc_writeb,
- .set_clock = esdhc_set_clock,
- .enable_dma = esdhc_enable_dma,
- .get_max_clock = esdhc_get_max_clock,
- .get_min_clock = esdhc_get_min_clock,
- },
-};
+#endif /* CONFIG_MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER */

#ifdef CONFIG_PM

@@ -301,9 +191,11 @@ static int __devexit sdhci_of_remove(struct of_device *ofdev)
}

static const struct of_device_id sdhci_of_match[] = {
+#ifdef CONFIG_MMC_SDHCI_OF_ESDHC
{ .compatible = "fsl,mpc8379-esdhc", .data = &sdhci_esdhc, },
{ .compatible = "fsl,mpc8536-esdhc", .data = &sdhci_esdhc, },
{ .compatible = "fsl,esdhc", .data = &sdhci_esdhc, },
+#endif
{ .compatible = "generic-sdhci", },
{},
};
diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
new file mode 100644
index 0000000..d5b11a1
--- /dev/null
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -0,0 +1,143 @@
+/*
+ * Freescale eSDHC controller driver.
+ *
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ * Copyright (c) 2009 MontaVista Software, Inc.
+ *
+ * Authors: Xiaobo Xie <X.Xie@freescale.com>
+ * Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * 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, or (at
+ * your option) any later version.
+ */
+
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/mmc/host.h>
+#include "sdhci-of.h"
+#include "sdhci.h"
+
+/*
+ * Ops and quirks for the Freescale eSDHC controller.
+ */
+
+#define ESDHC_DMA_SYSCTL 0x40c
+#define ESDHC_DMA_SNOOP 0x00000040
+
+#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
+
+#define ESDHC_HOST_CONTROL_RES 0x05
+
+static u16 esdhc_readw(struct sdhci_host *host, int reg)
+{
+ u16 ret;
+
+ if (unlikely(reg == SDHCI_HOST_VERSION))
+ ret = in_be16(host->ioaddr + reg);
+ else
+ ret = sdhci_be32bs_readw(host, reg);
+ return ret;
+}
+
+static void esdhc_writew(struct sdhci_host *host, u16 val, int reg)
+{
+ if (reg == SDHCI_BLOCK_SIZE) {
+ /*
+ * Two last DMA bits are reserved, and first one is used for
+ * non-standard blksz of 4096 bytes that we don't support
+ * yet. So clear the DMA boundary bits.
+ */
+ val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
+ }
+ sdhci_be32bs_writew(host, val, reg);
+}
+
+static void esdhc_writeb(struct sdhci_host *host, u8 val, int reg)
+{
+ /* Prevent SDHCI core from writing reserved bits (e.g. HISPD). */
+ if (reg == SDHCI_HOST_CONTROL)
+ val &= ~ESDHC_HOST_CONTROL_RES;
+ sdhci_be32bs_writeb(host, val, reg);
+}
+
+static void esdhc_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+ int pre_div = 2;
+ int div = 1;
+
+ clrbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
+ ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN | ESDHC_CLOCK_MASK);
+
+ 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--;
+
+ setbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
+ ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN |
+ div << ESDHC_DIVIDER_SHIFT | pre_div << ESDHC_PREDIV_SHIFT);
+ mdelay(100);
+out:
+ host->clock = clock;
+}
+
+static int esdhc_enable_dma(struct sdhci_host *host)
+{
+ setbits32(host->ioaddr + ESDHC_DMA_SYSCTL, ESDHC_DMA_SNOOP);
+ return 0;
+}
+
+static unsigned int esdhc_get_max_clock(struct sdhci_host *host)
+{
+ struct sdhci_of_host *of_host = sdhci_priv(host);
+
+ return of_host->clock;
+}
+
+static unsigned int esdhc_get_min_clock(struct sdhci_host *host)
+{
+ struct sdhci_of_host *of_host = sdhci_priv(host);
+
+ return of_host->clock / 256 / 16;
+}
+
+struct sdhci_of_data sdhci_esdhc = {
+ .quirks = SDHCI_QUIRK_FORCE_BLK_SZ_2048 |
+ SDHCI_QUIRK_BROKEN_CARD_DETECTION |
+ 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 |
+ SDHCI_QUIRK_NO_CARD_NO_RESET,
+ .ops = {
+ .readl = sdhci_be32bs_readl,
+ .readw = esdhc_readw,
+ .readb = sdhci_be32bs_readb,
+ .writel = sdhci_be32bs_writel,
+ .writew = esdhc_writew,
+ .writeb = esdhc_writeb,
+ .set_clock = esdhc_set_clock,
+ .enable_dma = esdhc_enable_dma,
+ .get_max_clock = esdhc_get_max_clock,
+ .get_min_clock = esdhc_get_min_clock,
+ },
+};
diff --git a/drivers/mmc/host/sdhci-of.h b/drivers/mmc/host/sdhci-of.h
new file mode 100644
index 0000000..17e873d
--- /dev/null
+++ b/drivers/mmc/host/sdhci-of.h
@@ -0,0 +1,41 @@
+/*
+ * OpenFirmware bindings for Secure Digital Host Controller Interface.
+ *
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ * Copyright (c) 2009 MontaVista Software, Inc.
+ *
+ * Authors: Xiaobo Xie <X.Xie@freescale.com>
+ * Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * 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, or (at
+ * your option) any later version.
+ */
+
+#ifndef __SDHCI_OF_H
+#define __SDHCI_OF_H
+
+#include <linux/types.h>
+#include "sdhci.h"
+
+struct sdhci_of_data {
+ unsigned int quirks;
+ struct sdhci_ops ops;
+};
+
+struct sdhci_of_host {
+ unsigned int clock;
+ u16 xfer_mode_shadow;
+};
+
+extern u32 sdhci_be32bs_readl(struct sdhci_host *host, int reg);
+extern u16 sdhci_be32bs_readw(struct sdhci_host *host, int reg);
+extern u8 sdhci_be32bs_readb(struct sdhci_host *host, int reg);
+extern void sdhci_be32bs_writel(struct sdhci_host *host, u32 val, int reg);
+extern void sdhci_be32bs_writew(struct sdhci_host *host, u16 val, int reg);
+extern void sdhci_be32bs_writeb(struct sdhci_host *host, u8 val, int reg);
+
+extern struct sdhci_of_data sdhci_esdhc;
+
+#endif /* __SDHCI_OF_H */
--
1.6.3.3