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

Thomas Chou
2015-10-30T13:33:46Z

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