mirror of
https://github.com/torvalds/linux.git
synced 2024-12-22 10:56:40 +00:00
a518d63777
This initial port adds support of ARC HS Development Kit board with some basic features such serial port, USB, SD/MMC and Ethernet. Essentially we run Linux kernel on all 4 cores (i.e. utilize SMP) and heavily use IO Coherency for speeding-up DMA-aware peripherals. Note as opposed to other ARC boards we link Linux kernel to 0x9000_0000 intentionally because cores 1 and 3 configured with DCCM situated at our more usual link base 0x8000_0000. We still can use memory region starting at 0x8000_0000 as we reallocate DCCM in our platform code. Note that PAE remapping for DMA clients does not work due to an RTL bug, so CREG_PAE register must be programmed to all zeroes, otherwise it will cause problems with DMA to/from peripherals even if PAE40 is not used. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
81 lines
2.0 KiB
C
81 lines
2.0 KiB
C
/*
|
|
* Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
|
|
*
|
|
* Based on reduced version of METAG
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_fdt.h>
|
|
#include <asm/mach_desc.h>
|
|
|
|
#ifdef CONFIG_SERIAL_EARLYCON
|
|
|
|
static unsigned int __initdata arc_base_baud;
|
|
|
|
unsigned int __init arc_early_base_baud(void)
|
|
{
|
|
return arc_base_baud/16;
|
|
}
|
|
|
|
static void __init arc_set_early_base_baud(unsigned long dt_root)
|
|
{
|
|
if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
|
|
arc_base_baud = 166666666; /* Fixed 166.6MHz clk (TB10x) */
|
|
else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") ||
|
|
of_flat_dt_is_compatible(dt_root, "snps,hsdk"))
|
|
arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x & HSDK) */
|
|
else if (of_flat_dt_is_compatible(dt_root, "ezchip,arc-nps"))
|
|
arc_base_baud = 800000000; /* Fixed 800MHz clk (NPS) */
|
|
else
|
|
arc_base_baud = 50000000; /* Fixed default 50MHz */
|
|
}
|
|
#else
|
|
#define arc_set_early_base_baud(dt_root)
|
|
#endif
|
|
|
|
static const void * __init arch_get_next_mach(const char *const **match)
|
|
{
|
|
static const struct machine_desc *mdesc = __arch_info_begin;
|
|
const struct machine_desc *m = mdesc;
|
|
|
|
if (m >= __arch_info_end)
|
|
return NULL;
|
|
|
|
mdesc++;
|
|
*match = m->dt_compat;
|
|
return m;
|
|
}
|
|
|
|
/**
|
|
* setup_machine_fdt - Machine setup when an dtb was passed to the kernel
|
|
* @dt: virtual address pointer to dt blob
|
|
*
|
|
* If a dtb was passed to the kernel, then use it to choose the correct
|
|
* machine_desc and to setup the system.
|
|
*/
|
|
const struct machine_desc * __init setup_machine_fdt(void *dt)
|
|
{
|
|
const struct machine_desc *mdesc;
|
|
unsigned long dt_root;
|
|
|
|
if (!early_init_dt_scan(dt))
|
|
return NULL;
|
|
|
|
mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach);
|
|
if (!mdesc)
|
|
machine_halt();
|
|
|
|
dt_root = of_get_flat_dt_root();
|
|
arc_set_early_base_baud(dt_root);
|
|
|
|
return mdesc;
|
|
}
|