| /* |
| * (C) Copyright 2010 |
| * Reinhard Meyer, EMK Elektronik, reinhard.meyer@emk-elektronik.de |
| * |
| * See file CREDITS for list of people who contributed to this |
| * project. |
| * |
| * 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. |
| * |
| * This program is distributed in the hope that 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, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| * MA 02111-1307 USA |
| */ |
| |
| /* |
| * Note: RAMTRON SPI FRAMs are ferroelectric, nonvolatile RAMs |
| * with an interface identical to SPI flash devices. |
| * However since they behave like RAM there are no delays or |
| * busy polls required. They can sustain read or write at the |
| * allowed SPI bus speed, which can be 40 MHz for some devices. |
| * |
| * Unfortunately some RAMTRON devices do not have a means of |
| * identifying them. They will leave the SO line undriven when |
| * the READ-ID command is issued. It is therefore mandatory |
| * that the MISO line has a proper pull-up, so that READ-ID |
| * will return a row of 0xff. This 0xff pseudo-id will cause |
| * probes by all vendor specific functions that are designed |
| * to handle it. If the MISO line is not pulled up, READ-ID |
| * could return any random noise, even mimicking another |
| * device. |
| * |
| * We use CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC |
| * to define which device will be assumed after a simple status |
| * register verify. This method is prone to false positive |
| * detection and should therefore be the last to be tried. |
| * Enter it in the last position in the table in spi_flash.c! |
| * |
| * The define CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC both activates |
| * compilation of the special handler and defines the device |
| * to assume. |
| */ |
| |
| #include <common.h> |
| #include <malloc.h> |
| #include <spi_flash.h> |
| #include "spi_flash_internal.h" |
| |
| /* RAMTRON commands common to all devices */ |
| #define CMD_RAMTRON_WREN 0x06 /* Write Enable */ |
| #define CMD_RAMTRON_WRDI 0x04 /* Write Disable */ |
| #define CMD_RAMTRON_RDSR 0x05 /* Read Status Register */ |
| #define CMD_RAMTRON_WRSR 0x01 /* Write Status Register */ |
| #define CMD_RAMTRON_READ 0x03 /* Read Data Bytes */ |
| #define CMD_RAMTRON_WRITE 0x02 /* Write Data Bytes */ |
| /* not all have those: */ |
| #define CMD_RAMTRON_FSTRD 0x0b /* Fast Read (for compatibility - not used here) */ |
| #define CMD_RAMTRON_SLEEP 0xb9 /* Enter Sleep Mode */ |
| #define CMD_RAMTRON_RDID 0x9f /* Read ID */ |
| #define CMD_RAMTRON_SNR 0xc3 /* Read Serial Number */ |
| |
| /* |
| * Properties of supported FRAMs |
| * Note: speed is currently not used because we have no method to deliver that |
| * value to the upper layers |
| */ |
| struct ramtron_spi_fram_params { |
| u32 size; /* size in bytes */ |
| u8 addr_len; /* number of address bytes */ |
| u8 merge_cmd; /* some address bits are in the command byte */ |
| u8 id1; /* device ID 1 (family, density) */ |
| u8 id2; /* device ID 2 (sub, rev, rsvd) */ |
| u32 speed; /* max. SPI clock in Hz */ |
| const char *name; /* name for display and/or matching */ |
| }; |
| |
| struct ramtron_spi_fram { |
| struct spi_flash flash; |
| const struct ramtron_spi_fram_params *params; |
| }; |
| |
| static inline struct ramtron_spi_fram *to_ramtron_spi_fram(struct spi_flash |
| *flash) |
| { |
| return container_of(flash, struct ramtron_spi_fram, flash); |
| } |
| |
| /* |
| * table describing supported FRAM chips: |
| * chips without RDID command must have the values 0xff for id1 and id2 |
| */ |
| static const struct ramtron_spi_fram_params ramtron_spi_fram_table[] = { |
| { |
| .size = 32*1024, |
| .addr_len = 2, |
| .merge_cmd = 0, |
| .id1 = 0x22, |
| .id2 = 0x00, |
| .speed = 40000000, |
| .name = "FM25V02", |
| }, |
| { |
| .size = 32*1024, |
| .addr_len = 2, |
| .merge_cmd = 0, |
| .id1 = 0x22, |
| .id2 = 0x01, |
| .speed = 40000000, |
| .name = "FM25VN02", |
| }, |
| { |
| .size = 64*1024, |
| .addr_len = 2, |
| .merge_cmd = 0, |
| .id1 = 0x23, |
| .id2 = 0x00, |
| .speed = 40000000, |
| .name = "FM25V05", |
| }, |
| { |
| .size = 64*1024, |
| .addr_len = 2, |
| .merge_cmd = 0, |
| .id1 = 0x23, |
| .id2 = 0x01, |
| .speed = 40000000, |
| .name = "FM25VN05", |
| }, |
| { |
| .size = 128*1024, |
| .addr_len = 3, |
| .merge_cmd = 0, |
| .id1 = 0x24, |
| .id2 = 0x00, |
| .speed = 40000000, |
| .name = "FM25V10", |
| }, |
| { |
| .size = 128*1024, |
| .addr_len = 3, |
| .merge_cmd = 0, |
| .id1 = 0x24, |
| .id2 = 0x01, |
| .speed = 40000000, |
| .name = "FM25VN10", |
| }, |
| #ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC |
| { |
| .size = 256*1024, |
| .addr_len = 3, |
| .merge_cmd = 0, |
| .id1 = 0xff, |
| .id2 = 0xff, |
| .speed = 40000000, |
| .name = "FM25H20", |
| }, |
| #endif |
| }; |
| |
| static int ramtron_common(struct spi_flash *flash, |
| u32 offset, size_t len, void *buf, u8 command) |
| { |
| struct ramtron_spi_fram *sn = to_ramtron_spi_fram(flash); |
| u8 cmd[4]; |
| int cmd_len; |
| int ret; |
| |
| if (sn->params->addr_len == 3 && sn->params->merge_cmd == 0) { |
| cmd[0] = command; |
| cmd[1] = offset >> 16; |
| cmd[2] = offset >> 8; |
| cmd[3] = offset; |
| cmd_len = 4; |
| } else if (sn->params->addr_len == 2 && sn->params->merge_cmd == 0) { |
| cmd[0] = command; |
| cmd[1] = offset >> 8; |
| cmd[2] = offset; |
| cmd_len = 3; |
| } else { |
| printf("SF: unsupported addr_len or merge_cmd\n"); |
| return -1; |
| } |
| |
| /* claim the bus */ |
| ret = spi_claim_bus(flash->spi); |
| if (ret) { |
| debug("SF: Unable to claim SPI bus\n"); |
| return ret; |
| } |
| |
| if (command == CMD_RAMTRON_WRITE) { |
| /* send WREN */ |
| ret = spi_flash_cmd_write_enable(flash); |
| if (ret < 0) { |
| debug("SF: Enabling Write failed\n"); |
| goto releasebus; |
| } |
| } |
| |
| /* do the transaction */ |
| if (command == CMD_RAMTRON_WRITE) |
| ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len, buf, len); |
| else |
| ret = spi_flash_cmd_read(flash->spi, cmd, cmd_len, buf, len); |
| if (ret < 0) |
| debug("SF: Transaction failed\n"); |
| |
| releasebus: |
| /* release the bus */ |
| spi_release_bus(flash->spi); |
| return ret; |
| } |
| |
| static int ramtron_read(struct spi_flash *flash, |
| u32 offset, size_t len, void *buf) |
| { |
| return ramtron_common(flash, offset, len, buf, |
| CMD_RAMTRON_READ); |
| } |
| |
| static int ramtron_write(struct spi_flash *flash, |
| u32 offset, size_t len, const void *buf) |
| { |
| return ramtron_common(flash, offset, len, (void *)buf, |
| CMD_RAMTRON_WRITE); |
| } |
| |
| static int ramtron_erase(struct spi_flash *flash, u32 offset, size_t len) |
| { |
| debug("SF: Erase of RAMTRON FRAMs is pointless\n"); |
| return -1; |
| } |
| |
| /* |
| * nore: we are called here with idcode pointing to the first non-0x7f byte |
| * already! |
| */ |
| struct spi_flash *spi_fram_probe_ramtron(struct spi_slave *spi, u8 *idcode) |
| { |
| const struct ramtron_spi_fram_params *params; |
| struct ramtron_spi_fram *sn; |
| unsigned int i; |
| #ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC |
| int ret; |
| u8 sr; |
| #endif |
| |
| /* NOTE: the bus has been claimed before this function is called! */ |
| switch (idcode[0]) { |
| case 0xc2: |
| /* JEDEC conformant RAMTRON id */ |
| for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) { |
| params = &ramtron_spi_fram_table[i]; |
| if (idcode[1] == params->id1 && idcode[2] == params->id2) |
| goto found; |
| } |
| break; |
| #ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC |
| case 0xff: |
| /* |
| * probably open MISO line, pulled up. |
| * We COULD have a non JEDEC conformant FRAM here, |
| * read the status register to verify |
| */ |
| ret = spi_flash_cmd(spi, CMD_RAMTRON_RDSR, &sr, 1); |
| if (ret) |
| return NULL; |
| |
| /* Bits 5,4,0 are fixed 0 for all devices */ |
| if ((sr & 0x31) != 0x00) |
| return NULL; |
| /* now find the device */ |
| for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) { |
| params = &ramtron_spi_fram_table[i]; |
| if (!strcmp(params->name, CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC)) |
| goto found; |
| } |
| debug("SF: Unsupported non-JEDEC RAMTRON device " |
| CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC "\n"); |
| break; |
| #endif |
| default: |
| break; |
| } |
| |
| /* arriving here means no method has found a device we can handle */ |
| debug("SF/ramtron: unsupported device id0=%02x id1=%02x id2=%02x\n", |
| idcode[0], idcode[1], idcode[2]); |
| return NULL; |
| |
| found: |
| sn = malloc(sizeof(*sn)); |
| if (!sn) { |
| debug("SF: Failed to allocate memory\n"); |
| return NULL; |
| } |
| |
| sn->params = params; |
| sn->flash.spi = spi; |
| sn->flash.name = params->name; |
| |
| sn->flash.write = ramtron_write; |
| sn->flash.read = ramtron_read; |
| sn->flash.erase = ramtron_erase; |
| sn->flash.size = params->size; |
| |
| return &sn->flash; |
| } |