diff options
Diffstat (limited to 'firmware/microblaze/usrp2p/spi_flash_read.c')
-rw-r--r-- | firmware/microblaze/usrp2p/spi_flash_read.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/firmware/microblaze/usrp2p/spi_flash_read.c b/firmware/microblaze/usrp2p/spi_flash_read.c new file mode 100644 index 000000000..1c65350f7 --- /dev/null +++ b/firmware/microblaze/usrp2p/spi_flash_read.c @@ -0,0 +1,100 @@ +/* -*- c++ -*- */ +/* + * Copyright 2009 Free Software Foundation, Inc. + * Copyright 2009 Ettus Research LLC + * + * 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 3 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, see <http://www.gnu.org/licenses/>. + */ + +#include "spi_flash_private.h" +#include <stdlib.h> // abort + +uint32_t +spi_flash_rdid(void) +{ + return spif_transact(SPI_TXRX, SPI_SS_FLASH, RDID_CMD << 24, 32, FLAGS) & 0xffffff; +} + +size_t +spi_flash_log2_sector_size(void) +{ + static size_t _spi_flash_log2_sector_size; + + if (_spi_flash_log2_sector_size != 0) + return _spi_flash_log2_sector_size; + + + uint32_t id = spi_flash_rdid(); + int type = (id >> 8) & 0xff; + int size = id & 0xff; + if (type != 0x20 || size < 22 || size > 24) + abort(); + + static unsigned char log2_sector_size[3] = { + 16, /* M25P32 */ + 16, /* M25P64 */ + 18, /* M25P128 */ + }; + + _spi_flash_log2_sector_size = log2_sector_size[size - 22]; + return _spi_flash_log2_sector_size; +} + +void +spi_flash_read(uint32_t flash_addr, size_t nbytes, void *buf) +{ + /* + * We explicitly control the slave select here (/S), so that we can + * do the entire read operation as a single transaction from + * device's point of view. (The most our SPI peripheral can transfer + * in a single shot is 16 bytes.) + */ + spif_wait(); + + spif_regs->ss = 0; + spif_regs->ctrl = FLAGS; // ASS is now clear and no chip select is enabled. + + /* + * Do the 5 byte instruction tranfer: + * FAST_READ_CMD, ADDR2, ADDR1, ADDR0, DUMMY + */ + spif_regs->txrx1 = FAST_READ_CMD; + spif_regs->txrx0 = ((flash_addr & 0x00ffffff) << 8); + spif_regs->ss = SPI_SS_FLASH; // assert chip select + spif_regs->ctrl = FLAGS | LEN(5 * 8); + spif_regs->ctrl = FLAGS | LEN(5 * 8) | SPI_CTRL_GO_BSY; + spif_wait(); + + /* + * Read up to 16 bytes at a time until done + */ + unsigned char *dst = (unsigned char *) buf; + size_t m; + for (size_t n = 0; n < nbytes; n += m, dst += m){ + spif_regs->ctrl = FLAGS | LEN(16 * 8); // xfer 16 bytes + spif_regs->ctrl = FLAGS | LEN(16 * 8) | SPI_CTRL_GO_BSY; + spif_wait(); + + uint32_t w[4]; + w[0] = spif_regs->txrx3; // txrx3 has first bits in it + w[1] = spif_regs->txrx2; + w[2] = spif_regs->txrx1; + w[3] = spif_regs->txrx0; + unsigned char *src = (unsigned char *) &w[0]; + m = min(nbytes - n, 16); + for (size_t i = 0; i < m; i++) + dst[i] = src[i]; + } + spif_regs->ss = 0; // deassert chip select +} |