mirror of https://gitee.com/openkylin/linux.git
73 lines
1.7 KiB
C
73 lines
1.7 KiB
C
/*
|
|
* SDK7786 FPGA SRAM Support.
|
|
*
|
|
* Copyright (C) 2010 Paul Mundt
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*/
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/types.h>
|
|
#include <linux/io.h>
|
|
#include <linux/string.h>
|
|
#include <mach/fpga.h>
|
|
#include <asm/sram.h>
|
|
#include <asm/sizes.h>
|
|
|
|
static int __init fpga_sram_init(void)
|
|
{
|
|
unsigned long phys;
|
|
unsigned int area;
|
|
void __iomem *vaddr;
|
|
int ret;
|
|
u16 data;
|
|
|
|
/* Enable FPGA SRAM */
|
|
data = fpga_read_reg(LCLASR);
|
|
data |= LCLASR_FRAMEN;
|
|
fpga_write_reg(data, LCLASR);
|
|
|
|
/*
|
|
* FPGA_SEL determines the area mapping
|
|
*/
|
|
area = (data & LCLASR_FPGA_SEL_MASK) >> LCLASR_FPGA_SEL_SHIFT;
|
|
if (unlikely(area == LCLASR_AREA_MASK)) {
|
|
pr_err("FPGA memory unmapped.\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
/*
|
|
* The memory itself occupies a 2KiB range at the top of the area
|
|
* immediately below the system registers.
|
|
*/
|
|
phys = (area << 26) + SZ_64M - SZ_4K;
|
|
|
|
/*
|
|
* The FPGA SRAM resides in translatable physical space, so set
|
|
* up a mapping prior to inserting it in to the pool.
|
|
*/
|
|
vaddr = ioremap(phys, SZ_2K);
|
|
if (unlikely(!vaddr)) {
|
|
pr_err("Failed remapping FPGA memory.\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
pr_info("Adding %dKiB of FPGA memory at 0x%08lx-0x%08lx "
|
|
"(area %d) to pool.\n",
|
|
SZ_2K >> 10, phys, phys + SZ_2K - 1, area);
|
|
|
|
ret = gen_pool_add(sram_pool, (unsigned long)vaddr, SZ_2K, -1);
|
|
if (unlikely(ret < 0)) {
|
|
pr_err("Failed adding memory\n");
|
|
iounmap(vaddr);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
postcore_initcall(fpga_sram_init);
|