linux/arch/powerpc/sysdev/fsl_85xx_l2ctlr.c
Harninder Rai 6db92cc9d0 powerpc/85xx: add cache-sram support
It adds cache-sram support in P1/P2 QorIQ platforms as under:

* A small abstraction over powerpc's remote heap allocator
* Exports mpc85xx_cache_sram_alloc()/free() APIs
* Supports only one contiguous SRAM window
* Drivers can do the following in Kconfig to use these APIs
    "select FSL_85XX_CACHE_SRAM if MPC85xx"
* Required SRAM size and the offset where SRAM should be mapped must be
  provided at kernel command line as :
    cache-sram-size=<value>
    cache-sram-offset=<offset>

Signed-off-by: Harninder Rai <harninder.rai@freescale.com>
Signed-off-by: Vivek Mahajan <vivek.mahajan@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2010-10-14 00:54:38 -05:00

232 lines
5.2 KiB
C

/*
* Copyright 2009-2010 Freescale Semiconductor, Inc.
*
* QorIQ (P1/P2) L2 controller init for Cache-SRAM instantiation
*
* Author: Vivek Mahajan <vivek.mahajan@freescale.com>
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/of_platform.h>
#include <asm/io.h>
#include "fsl_85xx_cache_ctlr.h"
static char *sram_size;
static char *sram_offset;
struct mpc85xx_l2ctlr __iomem *l2ctlr;
static long get_cache_sram_size(void)
{
unsigned long val;
if (!sram_size || (strict_strtoul(sram_size, 0, &val) < 0))
return -EINVAL;
return val;
}
static long get_cache_sram_offset(void)
{
unsigned long val;
if (!sram_offset || (strict_strtoul(sram_offset, 0, &val) < 0))
return -EINVAL;
return val;
}
static int __init get_size_from_cmdline(char *str)
{
if (!str)
return 0;
sram_size = str;
return 1;
}
static int __init get_offset_from_cmdline(char *str)
{
if (!str)
return 0;
sram_offset = str;
return 1;
}
__setup("cache-sram-size=", get_size_from_cmdline);
__setup("cache-sram-offset=", get_offset_from_cmdline);
static int __devinit mpc85xx_l2ctlr_of_probe(struct platform_device *dev,
const struct of_device_id *match)
{
long rval;
unsigned int rem;
unsigned char ways;
const unsigned int *prop;
unsigned int l2cache_size;
struct sram_parameters sram_params;
if (!dev->dev.of_node) {
dev_err(&dev->dev, "Device's OF-node is NULL\n");
return -EINVAL;
}
prop = of_get_property(dev->dev.of_node, "cache-size", NULL);
if (!prop) {
dev_err(&dev->dev, "Missing L2 cache-size\n");
return -EINVAL;
}
l2cache_size = *prop;
sram_params.sram_size = get_cache_sram_size();
if (sram_params.sram_size <= 0) {
dev_err(&dev->dev,
"Entire L2 as cache, Aborting Cache-SRAM stuff\n");
return -EINVAL;
}
sram_params.sram_offset = get_cache_sram_offset();
if (sram_params.sram_offset <= 0) {
dev_err(&dev->dev,
"Entire L2 as cache, provide a valid sram offset\n");
return -EINVAL;
}
rem = l2cache_size % sram_params.sram_size;
ways = LOCK_WAYS_FULL * sram_params.sram_size / l2cache_size;
if (rem || (ways & (ways - 1))) {
dev_err(&dev->dev, "Illegal cache-sram-size in command line\n");
return -EINVAL;
}
l2ctlr = of_iomap(dev->dev.of_node, 0);
if (!l2ctlr) {
dev_err(&dev->dev, "Can't map L2 controller\n");
return -EINVAL;
}
/*
* Write bits[0-17] to srbar0
*/
out_be32(&l2ctlr->srbar0,
sram_params.sram_offset & L2SRAM_BAR_MSK_LO18);
/*
* Write bits[18-21] to srbare0
*/
#ifdef CONFIG_PHYS_64BIT
out_be32(&l2ctlr->srbarea0,
(sram_params.sram_offset >> 32) & L2SRAM_BARE_MSK_HI4);
#endif
clrsetbits_be32(&l2ctlr->ctl, L2CR_L2E, L2CR_L2FI);
switch (ways) {
case LOCK_WAYS_EIGHTH:
setbits32(&l2ctlr->ctl,
L2CR_L2E | L2CR_L2FI | L2CR_SRAM_EIGHTH);
break;
case LOCK_WAYS_TWO_EIGHTH:
setbits32(&l2ctlr->ctl,
L2CR_L2E | L2CR_L2FI | L2CR_SRAM_QUART);
break;
case LOCK_WAYS_HALF:
setbits32(&l2ctlr->ctl,
L2CR_L2E | L2CR_L2FI | L2CR_SRAM_HALF);
break;
case LOCK_WAYS_FULL:
default:
setbits32(&l2ctlr->ctl,
L2CR_L2E | L2CR_L2FI | L2CR_SRAM_FULL);
break;
}
eieio();
rval = instantiate_cache_sram(dev, sram_params);
if (rval < 0) {
dev_err(&dev->dev, "Can't instantiate Cache-SRAM\n");
iounmap(l2ctlr);
return -EINVAL;
}
return 0;
}
static int __devexit mpc85xx_l2ctlr_of_remove(struct platform_device *dev)
{
BUG_ON(!l2ctlr);
iounmap(l2ctlr);
remove_cache_sram(dev);
dev_info(&dev->dev, "MPC85xx L2 controller unloaded\n");
return 0;
}
static struct of_device_id mpc85xx_l2ctlr_of_match[] = {
{
.compatible = "fsl,p2020-l2-cache-controller",
},
{
.compatible = "fsl,p2010-l2-cache-controller",
},
{
.compatible = "fsl,p1020-l2-cache-controller",
},
{
.compatible = "fsl,p1011-l2-cache-controller",
},
{
.compatible = "fsl,p1013-l2-cache-controller",
},
{
.compatible = "fsl,p1022-l2-cache-controller",
},
{},
};
static struct of_platform_driver mpc85xx_l2ctlr_of_platform_driver = {
.driver = {
.name = "fsl-l2ctlr",
.owner = THIS_MODULE,
.of_match_table = mpc85xx_l2ctlr_of_match,
},
.probe = mpc85xx_l2ctlr_of_probe,
.remove = __devexit_p(mpc85xx_l2ctlr_of_remove),
};
static __init int mpc85xx_l2ctlr_of_init(void)
{
return of_register_platform_driver(&mpc85xx_l2ctlr_of_platform_driver);
}
static void __exit mpc85xx_l2ctlr_of_exit(void)
{
of_unregister_platform_driver(&mpc85xx_l2ctlr_of_platform_driver);
}
subsys_initcall(mpc85xx_l2ctlr_of_init);
module_exit(mpc85xx_l2ctlr_of_exit);
MODULE_DESCRIPTION("Freescale MPC85xx L2 controller init");
MODULE_LICENSE("GPL v2");