[U-Boot] [PATCH v3 2/3] cfi_flash: convert to driver model

[Thomas Chou <thomas@wytron.com.tw>]

Convert cfi flash to driver model.

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.
v3
  change to MTD uclass.

 doc/device-tree-bindings/mtd/mtd-physmap.txt | 88 ++++++++++++++++++++++++++++
 drivers/mtd/Kconfig                          | 11 ++++
 drivers/mtd/cfi_flash.c                      | 69 ++++++++++++++++++++++
 drivers/mtd/cfi_mtd.c                        |  2 +-
 include/mtd/cfi_flash.h                      |  3 +
 5 files changed, 172 insertions(+), 1 deletion(-)
 create mode 100644 doc/device-tree-bindings/mtd/mtd-physmap.txt

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..4b8c489
--- /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 23dff48..367c4fe 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -8,6 +8,17 @@ config MTD
 	  flash, RAM and similar chips, often used for solid state file
 	  systems on embedded devices.
 
+config CFI_FLASH
+	bool "Enable Driver Model for CFI Flash driver"
+	depends on MTD
+	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.
+
 endmenu
 
 source "drivers/mtd/nand/Kconfig"
diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index fc7a878..a439d8b 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 <fdt_support.h>
 #include <asm/processor.h>
 #include <asm/io.h>
 #include <asm/byteorder.h>
@@ -47,6 +50,8 @@
  * reading and writing ... (yes there is such a Hardware).
  */
 
+DECLARE_GLOBAL_DATA_PTR;
+
 static uint flash_offset_cfi[2] = { FLASH_OFFSET_CFI, FLASH_OFFSET_CFI_ALT };
 #ifdef CONFIG_FLASH_CFI_MTD
 static uint flash_verbose = 1;
@@ -87,10 +92,19 @@ 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
+static phys_addr_t cfi_flash_base[CFI_MAX_FLASH_BANKS];
+
+phys_addr_t cfi_flash_bank_addr(int i)
+{
+	return cfi_flash_base[i];
+}
+#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)
 {
@@ -2315,6 +2329,7 @@ unsigned long flash_init (void)
 {
 	unsigned long size = 0;
 	int i;
+	struct udevice *dev;
 
 #ifdef CONFIG_SYS_FLASH_PROTECTION
 	/* read environment from EEPROM */
@@ -2322,6 +2337,14 @@ unsigned long flash_init (void)
 	getenv_f("unlock", s, sizeof(s));
 #endif
 
+#ifdef CONFIG_CFI_FLASH /* for driver model */
+	cfi_flash_num_flash_banks = 0;
+	/* probe every MTD device */
+	for (uclass_first_device(UCLASS_MTD, &dev);
+	     dev;
+	     uclass_next_device(&dev)) {
+	}
+#endif
 	/* Init: no FLASHes known */
 	for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; ++i) {
 		flash_info[i].flash_id = FLASH_UNKNOWN;
@@ -2398,3 +2421,49 @@ unsigned long flash_init (void)
 
 	return (size);
 }
+
+#ifdef CONFIG_CFI_FLASH /* for driver model */
+static int cfi_flash_probe(struct udevice *dev)
+{
+	const void *blob = gd->fdt_blob;
+	int node = dev->of_offset;
+	const fdt32_t *cell;
+	phys_addr_t addr;
+	int addrs, sizes;
+	int len, idx;
+
+	/* decode regs, there may be multiple reg tuples. */
+	addrs = fdt_address_cells(blob, node);
+	sizes = fdt_size_cells(blob, node);
+	cell = fdt_getprop(blob, node, "reg", &len);
+	if (!cell)
+		return -ENOENT;
+	idx = 0;
+	len /= sizeof(fdt32_t);
+	while (idx < len) {
+		addr = fdt_translate_address((void *)blob,
+					     node, cell + idx);
+		cfi_flash_base[cfi_flash_num_flash_banks++] = addr;
+		idx += addrs + sizes;
+	}
+	gd->bd->bi_flashstart = cfi_flash_base[0];
+#ifdef CONFIG_FLASH_CFI_MTD
+	dev->uclass_priv = &cfi_mtd_info[0];
+	cfi_mtd_info[0].udev = dev;
+#endif
+	return 0;
+}
+
+static const struct udevice_id cfi_flash_ids[] = {
+	{ .compatible = "cfi-flash" },
+	{ .compatible = "jedec-flash" },
+	{ }
+};
+
+U_BOOT_DRIVER(cfi_flash) = {
+	.name	= "cfi_flash",
+	.id	= UCLASS_MTD,
+	.of_match = cfi_flash_ids,
+	.probe = cfi_flash_probe,
+};
+#endif /* CONFIG_CFI_FLASH */
diff --git a/drivers/mtd/cfi_mtd.c b/drivers/mtd/cfi_mtd.c
index 709a486..dcd7ab0 100644
--- a/drivers/mtd/cfi_mtd.c
+++ b/drivers/mtd/cfi_mtd.c
@@ -15,7 +15,7 @@
 #include <linux/mtd/concat.h>
 #include <mtd/cfi_flash.h>
 
-static struct mtd_info cfi_mtd_info[CFI_MAX_FLASH_BANKS];
+struct mtd_info cfi_mtd_info[CFI_MAX_FLASH_BANKS];
 static char cfi_mtd_names[CFI_MAX_FLASH_BANKS][16];
 #ifdef CONFIG_MTD_CONCAT
 static char c_mtd_name[16];
diff --git a/include/mtd/cfi_flash.h b/include/mtd/cfi_flash.h
index 52572b9..c1632f3 100644
--- a/include/mtd/cfi_flash.h
+++ b/include/mtd/cfi_flash.h
@@ -8,6 +8,8 @@
 #ifndef __CFI_FLASH_H__
 #define __CFI_FLASH_H__
 
+#include <linux/mtd/mtd.h>
+
 #define FLASH_CMD_CFI			0x98
 #define FLASH_CMD_READ_ID		0x90
 #define FLASH_CMD_RESET			0xff
@@ -164,6 +166,7 @@ extern int cfi_flash_num_flash_banks;
 #else
 #define CFI_MAX_FLASH_BANKS	CONFIG_SYS_MAX_FLASH_BANKS
 #endif
+extern struct mtd_info cfi_mtd_info[];
 
 void flash_write_cmd(flash_info_t * info, flash_sect_t sect,
 		     uint offset, u32 cmd);
-- 
2.5.0