[U-Boot] [PATCH v2] dm: implement a cfi flash uclass

Thomas Chou
2015-10-11T07:30:28Z

Implement a cfi flash uclass to work with drivers/mtd/cfi-flash.c.
The flash base address is extracted from device tree, and passed
to cfi_flash_bank_addr().

The current code supports only one bank. It should be extended to
support multiple banks by decoding multiple "reg" tuples, eg,
reg = <0 0x00000000 0x02000000
0 0x02000000 0x02000000>;

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
---
v2
add dts binding.
add more help to Kconfig.
move struct platdata to top of file as Simon suggested.

common/board_r.c | 3 +
configs/nios2-generic_defconfig | 1 +
doc/device-tree-bindings/mtd/mtd-physmap.txt | 88 ++++++++++++++++++++++++++++
drivers/mtd/Kconfig | 16 +++++
drivers/mtd/Makefile | 1 +
drivers/mtd/cfi-flash-uclass.c | 70 ++++++++++++++++++++++
drivers/mtd/cfi_flash.c | 18 ++++++
include/cfi-flash.h | 27 +++++++++
include/dm/uclass-id.h | 1 +
9 files changed, 225 insertions(+)
create mode 100644 doc/device-tree-bindings/mtd/mtd-physmap.txt
create mode 100644 drivers/mtd/cfi-flash-uclass.c
create mode 100644 include/cfi-flash.h

diff --git a/common/board_r.c b/common/board_r.c
index a4facf8..fceaea6 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -38,6 +38,7 @@
#include <miiphy.h>
#endif
#include <mmc.h>
+#include <mtd/cfi_flash.h>
#include <nand.h>
#include <onenand_uboot.h>
#include <scsi.h>
@@ -348,6 +349,8 @@ static int initr_flash(void)
/* update start of FLASH memory */
#ifdef CONFIG_SYS_FLASH_BASE
bd->bi_flashstart = CONFIG_SYS_FLASH_BASE;
+#else
+ bd->bi_flashstart = cfi_flash_bank_addr(0);
#endif
/* size of FLASH memory (final value) */
bd->bi_flashsize = flash_size;
diff --git a/configs/nios2-generic_defconfig b/configs/nios2-generic_defconfig
index 3d404b2..7b504ba 100644
--- a/configs/nios2-generic_defconfig
+++ b/configs/nios2-generic_defconfig
@@ -18,6 +18,7 @@ CONFIG_NET_RANDOM_ETHADDR=y
CONFIG_ALTERA_PIO=y
CONFIG_MISC=y
CONFIG_ALTERA_SYSID=y
+CONFIG_CFI_FLASH=y
CONFIG_ALTERA_JTAG_UART=y
CONFIG_ALTERA_JTAG_UART_BYPASS=y
CONFIG_TIMER=y
diff --git a/doc/device-tree-bindings/mtd/mtd-physmap.txt b/doc/device-tree-bindings/mtd/mtd-physmap.txt
new file mode 100644
index 0000000..a04d6e8
--- /dev/null
+++ b/doc/device-tree-bindings/mtd/mtd-physmap.txt
@@ -0,0 +1,88 @@
+CFI or JEDEC memory-mapped NOR flash, MTD-RAM (NVRAM...)
+
+Flash chips (Memory Technology Devices) are often used for solid state
+file systems on embedded devices.
+
+ - compatible : should contain the specific model of mtd chip(s)
+ used, if known, followed by either "cfi-flash", "jedec-flash",
+ "mtd-ram" or "mtd-rom".
+ - reg : Address range(s) of the mtd chip(s)
+ It's possible to (optionally) define multiple "reg" tuples so that
+ non-identical chips can be described in one node.
+ - bank-width : Width (in bytes) of the bank. Equal to the
+ device width times the number of interleaved chips.
+ - device-width : (optional) Width of a single mtd chip. If
+ omitted, assumed to be equal to 'bank-width'.
+ - #address-cells, #size-cells : Must be present if the device has
+ sub-nodes representing partitions (see below). In this case
+ both #address-cells and #size-cells must be equal to 1.
+ - no-unaligned-direct-access: boolean to disable the default direct
+ mapping of the flash.
+ On some platforms (e.g. MPC5200) a direct 1:1 mapping may cause
+ problems with JFFS2 usage, as the local bus (LPB) doesn't support
+ unaligned accesses as implemented in the JFFS2 code via memcpy().
+ By defining "no-unaligned-direct-access", the flash will not be
+ exposed directly to the MTD users (e.g. JFFS2) any more.
+ - linux,mtd-name: allow to specify the mtd name for retro capability with
+ physmap-flash drivers as boot loader pass the mtd partition via the old
+ device name physmap-flash.
+ - use-advanced-sector-protection: boolean to enable support for the
+ advanced sector protection (Spansion: PPB - Persistent Protection
+ Bits) locking.
+
+For JEDEC compatible devices, the following additional properties
+are defined:
+
+ - vendor-id : Contains the flash chip's vendor id (1 byte).
+ - device-id : Contains the flash chip's device id (1 byte).
+
+For ROM compatible devices (and ROM fallback from cfi-flash), the following
+additional (optional) property is defined:
+
+ - erase-size : The chip's physical erase block size in bytes.
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Example:
+
+ flash at ff000000 {
+ compatible = "amd,am29lv128ml", "cfi-flash";
+ reg = <ff000000 01000000>;
+ bank-width = <4>;
+ device-width = <1>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ fs at 0 {
+ label = "fs";
+ reg = <0 f80000>;
+ };
+ firmware at f80000 {
+ label ="firmware";
+ reg = <f80000 80000>;
+ read-only;
+ };
+ };
+
+Here an example with multiple "reg" tuples:
+
+ flash at f0000000,0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "intel,PC48F4400P0VB", "cfi-flash";
+ reg = <0 0x00000000 0x02000000
+ 0 0x02000000 0x02000000>;
+ bank-width = <2>;
+ partition at 0 {
+ label = "test-part1";
+ reg = <0 0x04000000>;
+ };
+ };
+
+An example using SRAM:
+
+ sram at 2,0 {
+ compatible = "samsung,k6f1616u6a", "mtd-ram";
+ reg = <2 0 0x00200000>;
+ bank-width = <2>;
+ };
diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 59278d1..b1addb5 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -1,3 +1,19 @@
+menu "CFI Flash Support"
+
+config CFI_FLASH
+ bool "Enable Driver Model for CFI Flash driver"
+ depends on DM
+ help
+ The Common Flash Interface specification was developed by Intel,
+ AMD and other flash manufactures that provides a universal method
+ for probing the capabilities of flash devices. If you wish to
+ support any device that is CFI-compliant, you need to enable this
+ option. Visit <http://www.amd.com/products/nvd/overview/cfi.html>
+ for more information on CFI. This driver uses the same API as
+ drivers/mtd/cfi_flash.c. But now implemented by the uclass.
+
+endmenu
+
source "drivers/mtd/nand/Kconfig"

source "drivers/mtd/spi/Kconfig"
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile
index a623f4c..0bcc76c 100644
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -11,6 +11,7 @@ endif
obj-$(CONFIG_MTD_PARTITIONS) += mtdpart.o
obj-$(CONFIG_MTD_CONCAT) += mtdconcat.o
obj-$(CONFIG_HAS_DATAFLASH) += at45.o
+obj-$(CONFIG_CFI_FLASH) += cfi-flash-uclass.o
obj-$(CONFIG_FLASH_CFI_DRIVER) += cfi_flash.o
obj-$(CONFIG_FLASH_CFI_MTD) += cfi_mtd.o
obj-$(CONFIG_HAS_DATAFLASH) += dataflash.o
diff --git a/drivers/mtd/cfi-flash-uclass.c b/drivers/mtd/cfi-flash-uclass.c
new file mode 100644
index 0000000..62c914b
--- /dev/null
+++ b/drivers/mtd/cfi-flash-uclass.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <cfi-flash.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct cfi_flash_platdata {
+ phys_addr_t base;
+};
+
+/*
+ * Implement a cfi flash uclass to work with drivers/mtd/cfi-flash.c.
+ */
+
+phys_addr_t cfi_flash_get_base(struct udevice *dev)
+{
+ struct cfi_flash_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ return uc_priv->base;
+}
+
+UCLASS_DRIVER(cfi_flash) = {
+ .id = UCLASS_CFI_FLASH,
+ .name = "cfi_flash",
+ .per_device_auto_alloc_size = sizeof(struct cfi_flash_dev_priv),
+};
+
+static int cfi_flash_probe(struct udevice *dev)
+{
+ struct cfi_flash_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+ struct cfi_flash_platdata *plat = dev->platdata;
+
+ uc_priv->base = plat->base;
+
+ return 0;
+}
+
+static int cfi_flash_ofdata_to_platdata(struct udevice *dev)
+{
+ struct cfi_flash_platdata *plat = dev_get_platdata(dev);
+ fdt_size_t size;
+
+ fdtdec_get_addr_size(gd->fdt_blob, dev->of_offset, "reg", &size);
+ plat->base = (phys_addr_t)ioremap(dev_get_addr(dev), size);
+
+ return 0;
+}
+
+static const struct udevice_id cfi_flash_ids[] = {
+ { .compatible = "cfi-flash", },
+ { }
+};
+
+U_BOOT_DRIVER(cfi_flash) = {
+ .name = "cfi_flash",
+ .id = UCLASS_CFI_FLASH,
+ .of_match = cfi_flash_ids,
+ .ofdata_to_platdata = cfi_flash_ofdata_to_platdata,
+ .platdata_auto_alloc_size = sizeof(struct cfi_flash_platdata),
+ .probe = cfi_flash_probe,
+};
diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index 50983b8..9204596 100644
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -18,6 +18,9 @@
/* #define DEBUG */

#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <cfi-flash.h>
#include <asm/processor.h>
#include <asm/io.h>
#include <asm/byteorder.h>
@@ -87,10 +90,25 @@ static u16 cfi_flash_config_reg(int i)
int cfi_flash_num_flash_banks = CONFIG_SYS_MAX_FLASH_BANKS_DETECT;
#endif

+#ifdef CONFIG_CFI_FLASH
+phys_addr_t cfi_flash_bank_addr(int i)
+{
+ struct udevice *dev;
+ int ret;
+
+ /* FIXME: the current code supports only one bank */
+ ret = uclass_get_device(UCLASS_CFI_FLASH, i, &dev);
+ if (ret)
+ return ret;
+
+ return cfi_flash_get_base(dev);
+}
+#else
__weak phys_addr_t cfi_flash_bank_addr(int i)
{
return ((phys_addr_t [])CONFIG_SYS_FLASH_BANKS_LIST)[i];
}
+#endif

__weak unsigned long cfi_flash_bank_size(int i)
{
diff --git a/include/cfi-flash.h b/include/cfi-flash.h
new file mode 100644
index 0000000..192df97
--- /dev/null
+++ b/include/cfi-flash.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef _CFI_FLASH_H_
+#define _CFI_FLASH_H_
+
+/*
+ * Get the cfi flash base address
+ *
+ * @dev: The cfi flash device
+ * @return: the cfi flash base address
+ */
+phys_addr_t cfi_flash_get_base(struct udevice *dev);
+
+/*
+ * struct cfi_flash_dev_priv - information about a device used by the uclass
+ *
+ * @base: the cfi flash base address
+ */
+struct cfi_flash_dev_priv {
+ phys_addr_t base;
+};
+
+#endif /* _CFI_FLASH_H_ */
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index a6982ab..09e370c 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -25,6 +25,7 @@ enum uclass_id {
UCLASS_SIMPLE_BUS, /* bus with child devices */

/* U-Boot uclasses start here - in alphabetical order */
+ UCLASS_CFI_FLASH, /* cfi flash */
UCLASS_CLK, /* Clock source, e.g. used by peripherals */
UCLASS_CPU, /* CPU, typically part of an SoC */
UCLASS_CROS_EC, /* Chrome OS EC */
--
2.1.4