diff options
author | Duncan Laurie <dlaurie@chromium.org> | 2012-10-11 13:04:14 -0700 |
---|---|---|
committer | Ronald G. Minnich <rminnich@gmail.com> | 2012-11-12 17:09:59 +0100 |
commit | d4bc0679540842d78712b41707c2da9f3d7ae204 (patch) | |
tree | 30ef0888bd8fec4b86759769bf7bad5477376baf /src/southbridge/intel/bd82x6x/early_spi.c | |
parent | 215f27856399b1e4cfe30268fad61bf821af3c19 (diff) |
SPI: Add early romstage SPI driver using hardware sequencing
This is a basic romstage driver that can be used for the
MRC cache code on systems where we do not have the MRC cache
stored in a flash region that is memory mapped.
It uses the hardware sequencing interface to avoid having
to know anything about the flash chip itself.
BUG=chrome-os-partner:15031
BRANCH=stout
TEST=manual: this was tested with debug code added to romstage
that attempted to read the MRC cache at offset 0x3e0000.
SPI READ offset=003e0000 size=64 buffer=ff7fba00
SPI ADDR 0x003e0000
SPI HSFC 0x3f00
SPI READ: 0=4443524d
SPI READ: 1=00000bb0
SPI READ: 2=00008e24
SPI READ: 3=00000000
SPI READ: 4=001c8bbb
SPI READ: 5=0c206466
SPI READ: 6=0a043220
SPI READ: 7=000058b4
SPI READ: 8=00000000
SPI READ: 9=00000000
SPI READ: 10=00100000
SPI READ: 11=00100005
SPI READ: 12=20202025
SPI READ: 13=000e0001
SPI READ: 14=00000000
SPI READ: 15=00000000
Change-Id: I5f78f53111f912ff5dda52bbf90fdc1824b82681
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/1777
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/southbridge/intel/bd82x6x/early_spi.c')
-rw-r--r-- | src/southbridge/intel/bd82x6x/early_spi.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/src/southbridge/intel/bd82x6x/early_spi.c b/src/southbridge/intel/bd82x6x/early_spi.c new file mode 100644 index 0000000000..8fe5161595 --- /dev/null +++ b/src/southbridge/intel/bd82x6x/early_spi.c @@ -0,0 +1,115 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2012 Google Inc. All rights reserved. + * + * 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; version 2 of + * the License. + * + * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <arch/io.h> +#include <arch/romcc_io.h> +#include <console/console.h> +#include <device/pci_ids.h> +#include <device/pci_def.h> +#include <delay.h> +#include "pch.h" + +#define SPI_DELAY 10 /* 10us */ +#define SPI_RETRY 200000 /* 2s */ + +static int early_spi_read_block(u32 offset, u8 size, u8 *buffer) +{ + u32 *ptr32 = (u32*)buffer; + u32 i; + + /* Clear status bits */ + RCBA16(SPIBAR_HSFS) |= SPIBAR_HSFS_AEL | SPIBAR_HSFS_FCERR | + SPIBAR_HSFS_FDONE; + + if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_SCIP) { + printk(BIOS_ERR, "SPI ERROR: transaction in progress\n"); + return -1; + } + + /* Set flash address */ + RCBA32(SPIBAR_FADDR) = offset; + + /* Setup read transaction */ + RCBA16(SPIBAR_HSFC) = SPIBAR_HSFC_BYTE_COUNT(size) | + SPIBAR_HSFC_CYCLE_READ; + + /* Start transactinon */ + RCBA16(SPIBAR_HSFC) |= SPIBAR_HSFC_GO; + + /* Wait for completion */ + for (i = 0; i < SPI_RETRY; i++) { + if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_SCIP) { + /* Cycle in progress, wait 1ms */ + udelay(SPI_DELAY); + continue; + } + + if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_AEL) { + printk(BIOS_ERR, "SPI ERROR: Access Error\n"); + return -1; + + } + + if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_FCERR) { + printk(BIOS_ERR, "SPI ERROR: Flash Cycle Error\n"); + return -1; + } + break; + } + + if (i >= SPI_RETRY) { + printk(BIOS_ERR, "SPI ERROR: Timeout\n"); + return -1; + } + + /* Read the data */ + for (i = 0; i < size; i+=sizeof(u32)) { + if (size-i >= 4) { + /* reading >= dword */ + *ptr32++ = RCBA32(SPIBAR_FDATA(i/sizeof(u32))); + } else { + /* reading < dword */ + u8 j, *ptr8 = (u8*)ptr32; + u32 temp = RCBA32(SPIBAR_FDATA(i/sizeof(u32))); + for (j = 0; j < (size-i); j++) { + *ptr8++ = temp & 0xff; + temp >>= 8; + } + } + } + + return size; +} + +int early_spi_read(u32 offset, u32 size, u8 *buffer) +{ + u32 current = 0; + + while (size > 0) { + u8 count = (size < 64) ? size : 64; + if (early_spi_read_block(offset + current, count, + buffer + current) < 0) + return -1; + size -= count; + current += count; + } + + return 0; +} |