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baytrail: enable caching and prefetching in spi controller 

The default mode of the SPI controller has prefetching disabled.
That obviously has a performance impact. Enable both caching
and prefetching to make booting faster. This has a significant
impact on streaming data out of SPI.

BUG=chrome-os-partner:24085
BRANCH=None
TEST=Built and booted rambi. Payload loading step went from ~285ms
     to ~54ms.

Change-Id: I065cf44e1de7dcefc49aa9ea9ad0204929ab26f4
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/177220
Reviewed-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: http://review.coreboot.org/4976
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
This commit is contained in:
Aaron Durbin 2013-11-18 11:16:20 -06:00 committed by Kyösti Mälkki
parent bd4ea8cd4d
commit 6f9947a3ec
2 changed files with 41 additions and 0 deletions
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31
src/soc/intel/baytrail/baytrail/spi.h Normal file
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@ -0,0 +1,31 @@
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2013 Google Inc.
*
* 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
*/
#ifndef _BAYTRAIL_SPI_H_
#define _BAYTRAIL_SPI_H_
/* These registers live behind SPI_BASE_ADDRESS. */
#define BCR 0xfc
# define SRC_MASK (0x3 << 2)
# define SRC_CACHE_NO_PREFETCH (0x0 << 2)
# define SRC_NO_CACHE_NO_PREFETCH (0x1 << 2)
# define SRC_CACHE_PREFETCH (0x2 << 2)
#endif /* _BAYTRAIL_SPI_H_ */

10
src/soc/intel/baytrail/romstage/romstage.c
View File

@ -41,6 +41,7 @@
#include <baytrail/reset.h>
#include <baytrail/romstage.h>
#include <baytrail/smm.h>
#include <baytrail/spi.h>
static inline uint64_t timestamp_get(void)
{
@ -94,6 +95,13 @@ static void program_base_addresses(void)
pci_write_config32(lpc_dev, GBASE, reg);
}
static void spi_init(void)
{
const unsigned long bcr = SPI_BASE_ADDRESS + BCR;
/* Enable caching and prefetching in the SPI controller. */
write32(bcr, (read32(bcr) & ~SRC_MASK) | SRC_CACHE_PREFETCH);
}
static inline void mark_ts(struct romstage_params *rp, uint64_t ts)
{
struct romstage_timestamps *rt = &rp->ts;
@ -124,6 +132,8 @@ void * asmlinkage romstage_main(unsigned long bist,
console_init();
spi_init();
set_max_freq();
punit_init();