mirror of https://gitee.com/openkylin/linux.git
85 lines
1.9 KiB
C
85 lines
1.9 KiB
C
/*
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* Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
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*
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* Based on reduced version of METAG
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/init.h>
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#include <linux/reboot.h>
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#include <linux/memblock.h>
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#include <linux/of.h>
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#include <linux/of_fdt.h>
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#include <asm/clk.h>
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#include <asm/mach_desc.h>
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#ifdef CONFIG_SERIAL_EARLYCON
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static unsigned int __initdata arc_base_baud;
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unsigned int __init arc_early_base_baud(void)
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{
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return arc_base_baud/16;
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}
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static void __init arc_set_early_base_baud(unsigned long dt_root)
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{
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unsigned int core_clk = arc_get_core_freq();
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if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
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arc_base_baud = core_clk/3;
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else
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arc_base_baud = core_clk;
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}
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#else
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#define arc_set_early_base_baud(dt_root)
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#endif
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static const void * __init arch_get_next_mach(const char *const **match)
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{
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static const struct machine_desc *mdesc = __arch_info_begin;
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const struct machine_desc *m = mdesc;
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if (m >= __arch_info_end)
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return NULL;
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mdesc++;
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*match = m->dt_compat;
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return m;
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}
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/**
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* setup_machine_fdt - Machine setup when an dtb was passed to the kernel
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* @dt: virtual address pointer to dt blob
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*
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* If a dtb was passed to the kernel, then use it to choose the correct
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* machine_desc and to setup the system.
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*/
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const struct machine_desc * __init setup_machine_fdt(void *dt)
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{
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const struct machine_desc *mdesc;
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unsigned long dt_root;
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const void *clk;
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int len;
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if (!early_init_dt_scan(dt))
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return NULL;
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mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach);
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if (!mdesc)
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machine_halt();
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dt_root = of_get_flat_dt_root();
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clk = of_get_flat_dt_prop(dt_root, "clock-frequency", &len);
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if (clk)
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arc_set_core_freq(of_read_ulong(clk, len/4));
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arc_set_early_base_baud(dt_root);
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return mdesc;
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}
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