linuxdebug/arch/sh/boards/mach-sdk7786/fpga.c

70 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* SDK7786 FPGA Support.
*
* Copyright (C) 2010 Paul Mundt
*/
#include <linux/init.h>
#include <linux/io.h>
#include <linux/bcd.h>
#include <mach/fpga.h>
#include <linux/sizes.h>
#define FPGA_REGS_OFFSET 0x03fff800
#define FPGA_REGS_SIZE 0x490
/*
* The FPGA can be mapped in any of the generally available areas,
* so we attempt to scan for it using the fixed SRSTR read magic.
*
* Once the FPGA is located, the rest of the mapping data for the other
* components can be determined dynamically from its section mapping
* registers.
*/
static void __iomem *sdk7786_fpga_probe(void)
{
unsigned long area;
void __iomem *base;
/*
* Iterate over all of the areas where the FPGA could be mapped.
* The possible range is anywhere from area 0 through 6, area 7
* is reserved.
*/
for (area = PA_AREA0; area < PA_AREA7; area += SZ_64M) {
base = ioremap(area + FPGA_REGS_OFFSET, FPGA_REGS_SIZE);
if (!base) {
/* Failed to remap this area, move along. */
continue;
}
if (ioread16(base + SRSTR) == SRSTR_MAGIC)
return base; /* Found it! */
iounmap(base);
}
return NULL;
}
void __iomem *sdk7786_fpga_base;
void __init sdk7786_fpga_init(void)
{
u16 version, date;
sdk7786_fpga_base = sdk7786_fpga_probe();
if (unlikely(!sdk7786_fpga_base)) {
panic("FPGA detection failed.\n");
return;
}
version = fpga_read_reg(FPGAVR);
date = fpga_read_reg(FPGADR);
pr_info("\tFPGA version:\t%d.%d (built on %d/%d/%d)\n",
bcd2bin(version >> 8) & 0xf, bcd2bin(version & 0xf),
((date >> 12) & 0xf) + 2000,
(date >> 8) & 0xf, bcd2bin(date & 0xff));
}