diff options
author | Lee Jones <lee.jones@linaro.org> | 2014-03-20 09:20:44 +0000 |
---|---|---|
committer | Brian Norris <computersforpeace@gmail.com> | 2014-03-20 04:17:16 -0700 |
commit | 97ccf2d253cd211d3922a30bde5d4adf9080fb8a (patch) | |
tree | 7f8434929934377f348bdb92a1bd72088f1fe221 /drivers/mtd/devices | |
parent | 3b5d1981933b25973b02684dccb17d4282fd4d6d (diff) |
mtd: st_spi_fsm: Prepare the read/write FSM message sequence(s)
The FSM Serial Flash Controller is driven by issuing a standard set of
register writes we call a message sequence. This patch supplies a method
to prepare read/write FSM message sequence(s) based on chip capability
and configuration.
Acked-by Angus Clark <angus.clark@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Diffstat (limited to 'drivers/mtd/devices')
-rw-r--r-- | drivers/mtd/devices/st_spi_fsm.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c index 5a1b470ce908..83cf9dfd02e7 100644 --- a/drivers/mtd/devices/st_spi_fsm.c +++ b/drivers/mtd/devices/st_spi_fsm.c @@ -489,6 +489,75 @@ stfsm_search_seq_rw_configs(struct stfsm *fsm, return NULL; } +/* Prepare a READ/WRITE sequence according to configuration parameters */ +static void stfsm_prepare_rw_seq(struct stfsm *fsm, + struct stfsm_seq *seq, + struct seq_rw_config *cfg) +{ + int addr1_cycles, addr2_cycles; + int i = 0; + + memset(seq, 0, sizeof(*seq)); + + /* Add READ/WRITE OPC */ + seq->seq_opc[i++] = (SEQ_OPC_PADS_1 | + SEQ_OPC_CYCLES(8) | + SEQ_OPC_OPCODE(cfg->cmd)); + + /* Add WREN OPC for a WRITE sequence */ + if (cfg->write) + seq->seq_opc[i++] = (SEQ_OPC_PADS_1 | + SEQ_OPC_CYCLES(8) | + SEQ_OPC_OPCODE(FLASH_CMD_WREN) | + SEQ_OPC_CSDEASSERT); + + /* Address configuration (24 or 32-bit addresses) */ + addr1_cycles = (fsm->info->flags & FLASH_FLAG_32BIT_ADDR) ? 16 : 8; + addr1_cycles /= cfg->addr_pads; + addr2_cycles = 16 / cfg->addr_pads; + seq->addr_cfg = ((addr1_cycles & 0x3f) << 0 | /* ADD1 cycles */ + (cfg->addr_pads - 1) << 6 | /* ADD1 pads */ + (addr2_cycles & 0x3f) << 16 | /* ADD2 cycles */ + ((cfg->addr_pads - 1) << 22)); /* ADD2 pads */ + + /* Data/Sequence configuration */ + seq->seq_cfg = ((cfg->data_pads - 1) << 16 | + SEQ_CFG_STARTSEQ | + SEQ_CFG_CSDEASSERT); + if (!cfg->write) + seq->seq_cfg |= SEQ_CFG_READNOTWRITE; + + /* Mode configuration (no. of pads taken from addr cfg) */ + seq->mode = ((cfg->mode_data & 0xff) << 0 | /* data */ + (cfg->mode_cycles & 0x3f) << 16 | /* cycles */ + (cfg->addr_pads - 1) << 22); /* pads */ + + /* Dummy configuration (no. of pads taken from addr cfg) */ + seq->dummy = ((cfg->dummy_cycles & 0x3f) << 16 | /* cycles */ + (cfg->addr_pads - 1) << 22); /* pads */ + + + /* Instruction sequence */ + i = 0; + if (cfg->write) + seq->seq[i++] = STFSM_INST_CMD2; + + seq->seq[i++] = STFSM_INST_CMD1; + + seq->seq[i++] = STFSM_INST_ADD1; + seq->seq[i++] = STFSM_INST_ADD2; + + if (cfg->mode_cycles) + seq->seq[i++] = STFSM_INST_MODE; + + if (cfg->dummy_cycles) + seq->seq[i++] = STFSM_INST_DUMMY; + + seq->seq[i++] = + cfg->write ? STFSM_INST_DATA_WRITE : STFSM_INST_DATA_READ; + seq->seq[i++] = STFSM_INST_STOP; +} + static void stfsm_read_jedec(struct stfsm *fsm, uint8_t *const jedec) { const struct stfsm_seq *seq = &stfsm_seq_read_jedec; |