ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init
authorVineet Gupta <vgupta@synopsys.com>
Fri, 18 Jan 2013 09:42:20 +0000 (15:12 +0530)
committerVineet Gupta <vgupta@synopsys.com>
Fri, 15 Feb 2013 17:45:54 +0000 (23:15 +0530)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
arch/arc/Kconfig
arch/arc/include/asm/arcregs.h
arch/arc/include/asm/setup.h [new file with mode: 0644]
arch/arc/kernel/head.S [new file with mode: 0644]
arch/arc/kernel/reset.c [new file with mode: 0644]
arch/arc/kernel/setup.c [new file with mode: 0644]
arch/arc/mm/init.c [new file with mode: 0644]
arch/arc/plat-arcfpga/platform.c [new file with mode: 0644]

index 756beff..a353849 100644 (file)
@@ -23,7 +23,9 @@ config ARC
        select GENERIC_SIGALTSTACK
        select GENERIC_SMP_IDLE_THREAD
        select HAVE_GENERIC_HARDIRQS
+       select HAVE_MEMBLOCK
        select MODULES_USE_ELF_RELA
+       select NO_BOOTMEM
 
 config SCHED_OMIT_FRAME_POINTER
        def_bool y
index 1c24485..9e42611 100644 (file)
        }                                               \
 }
 
+/* Helpers */
+#define TO_KB(bytes)           ((bytes) >> 10)
+#define TO_MB(bytes)           (TO_KB(bytes) >> 10)
+#define PAGES_TO_KB(n_pages)   ((n_pages) << (PAGE_SHIFT - 10))
+#define PAGES_TO_MB(n_pages)   (PAGES_TO_KB(n_pages) >> 10)
 
 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
 /* These DPFP regs need to be saved/restored across ctx-sw */
diff --git a/arch/arc/include/asm/setup.h b/arch/arc/include/asm/setup.h
new file mode 100644 (file)
index 0000000..ab427e6
--- /dev/null
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ */
+
+#ifndef __ASMARC_SETUP_H
+#define __ASMARC_SETUP_H
+
+#include <linux/types.h>
+
+#define COMMAND_LINE_SIZE 256
+
+extern int root_mountflags, end_mem;
+extern int running_on_hw;
+
+void __init setup_processor(void);
+void __init setup_arch_memory(void);
+
+#endif /* __ASMARC_SETUP_H */
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
new file mode 100644 (file)
index 0000000..e63f6a4
--- /dev/null
@@ -0,0 +1,78 @@
+/*
+ * ARC CPU startup Code
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ *
+ * Vineetg: Dec 2007
+ *  -Check if we are running on Simulator or on real hardware
+ *      to skip certain things during boot on simulator
+ */
+
+#include <asm/asm-offsets.h>
+#include <asm/entry.h>
+#include <linux/linkage.h>
+#include <asm/arcregs.h>
+
+       .cpu A7
+
+       .section .init.text, "ax",@progbits
+       .type stext, @function
+       .globl stext
+stext:
+       ;-------------------------------------------------------------------
+       ; Don't clobber r0-r4 yet. It might have bootloader provided info
+       ;-------------------------------------------------------------------
+
+       ; Clear BSS before updating any globals
+       ; XXX: use ZOL here
+       mov     r5, __bss_start
+       mov     r6, __bss_stop
+1:
+       st.ab   0, [r5,4]
+       brlt    r5, r6, 1b
+
+#ifdef CONFIG_CMDLINE_UBOOT
+       ; support for bootloader provided cmdline
+       ;    If cmdline passed by u-boot, then
+       ;    r0 = 1  (because ATAGS parsing, now retired, used to use 0)
+       ;    r1 = magic number (board identity)
+       ;    r2 = addr of cmdline string (somewhere in memory/flash)
+
+       brne    r0, 1, .Lother_bootup_chores    ; u-boot didn't pass cmdline
+       breq    r2, 0, .Lother_bootup_chores    ; or cmdline is NULL
+
+       mov     r5, @command_line
+1:
+       ldb.ab  r6, [r2, 1]
+       breq    r6, 0, .Lother_bootup_chores
+       b.d     1b
+       stb.ab  r6, [r5, 1]
+#endif
+
+.Lother_bootup_chores:
+
+       ; Identify if running on ISS vs Silicon
+       ;       IDENTITY Reg [ 3  2  1  0 ]
+       ;       (chip-id)      ^^^^^            ==> 0xffff for ISS
+       lr      r0, [identity]
+       lsr     r3, r0, 16
+       cmp     r3, 0xffff
+       mov.z   r4, 0
+       mov.nz  r4, 1
+       st      r4, [@running_on_hw]
+
+       ; setup "current" tsk and optionally cache it in dedicated r25
+       mov     r9, @init_task
+       SET_CURR_TASK_ON_CPU  r9, r0    ; r9 = tsk, r0 = scratch
+
+       ; setup stack (fp, sp)
+       mov     fp, 0
+
+       ; tsk->thread_info is really a PAGE, whose bottom hoists stack
+       GET_TSK_STACK_BASE r9, sp       ; r9 = tsk, sp = stack base(output)
+
+       j       start_kernel    ; "C" entry point
diff --git a/arch/arc/kernel/reset.c b/arch/arc/kernel/reset.c
new file mode 100644 (file)
index 0000000..e227a2b
--- /dev/null
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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/kernel.h>
+#include <linux/printk.h>
+#include <linux/reboot.h>
+#include <linux/pm.h>
+
+void machine_halt(void)
+{
+       /* Halt the processor */
+       __asm__ __volatile__("flag  1\n");
+}
+
+void machine_restart(char *__unused)
+{
+       /* Soft reset : jump to reset vector */
+       pr_info("Put your restart handler here\n");
+       machine_halt();
+}
+
+void machine_power_off(void)
+{
+       /* FIXME ::  power off ??? */
+       machine_halt();
+}
+
+void (*pm_power_off) (void) = NULL;
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
new file mode 100644 (file)
index 0000000..82ac206
--- /dev/null
@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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/seq_file.h>
+#include <linux/fs.h>
+#include <linux/delay.h>
+#include <linux/root_dev.h>
+#include <linux/console.h>
+#include <linux/module.h>
+#include <linux/cpu.h>
+#include <asm/arcregs.h>
+#include <asm/tlb.h>
+#include <asm/cache.h>
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/irq.h>
+#include <asm/arcregs.h>
+
+#define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
+
+int running_on_hw = 1; /* vs. on ISS */
+
+char __initdata command_line[COMMAND_LINE_SIZE];
+
+struct task_struct *_current_task[NR_CPUS];    /* For stack switching */
+
+struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
+
+void __init read_arc_build_cfg_regs(void)
+{
+       read_decode_mmu_bcr();
+       read_decode_cache_bcr();
+}
+
+/*
+ * Initialize and setup the processor core
+ * This is called by all the CPUs thus should not do special case stuff
+ *    such as only for boot CPU etc
+ */
+
+void __init setup_processor(void)
+{
+       read_arc_build_cfg_regs();
+       arc_init_IRQ();
+       arc_mmu_init();
+       arc_cache_init();
+}
+
+void __init __attribute__((weak)) arc_platform_early_init(void)
+{
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+#ifdef CONFIG_CMDLINE_UBOOT
+       /* Make sure that a whitespace is inserted before */
+       strlcat(command_line, " ", sizeof(command_line));
+#endif
+       /*
+        * Append .config cmdline to base command line, which might already
+        * contain u-boot "bootargs" (handled by head.S, if so configured)
+        */
+       strlcat(command_line, CONFIG_CMDLINE, sizeof(command_line));
+
+       /* Save unparsed command line copy for /proc/cmdline */
+       strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
+       *cmdline_p = command_line;
+
+       /* To force early parsing of things like mem=xxx */
+       parse_early_param();
+
+       /* Platform/board specific: e.g. early console registration */
+       arc_platform_early_init();
+
+       setup_processor();
+
+       setup_arch_memory();
+
+       /* Can be issue if someone passes cmd line arg "ro"
+        * But that is unlikely so keeping it as it is
+        */
+       root_mountflags &= ~MS_RDONLY;
+
+       console_verbose();
+
+#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
+       conswitchp = &dummy_con;
+#endif
+
+}
+
+/*
+ *  Get CPU information for use by the procfs.
+ */
+
+#define cpu_to_ptr(c)  ((void *)(0xFFFF0000 | (unsigned int)(c)))
+#define ptr_to_cpu(p)  (~0xFFFF0000UL & (unsigned int)(p))
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+       char *str;
+       int cpu_id = ptr_to_cpu(v);
+
+       str = (char *)__get_free_page(GFP_TEMPORARY);
+       if (!str)
+               goto done;
+
+       seq_printf(m, "ARC700 #%d\n", cpu_id);
+
+       seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n",
+                  loops_per_jiffy / (500000 / HZ),
+                  (loops_per_jiffy / (5000 / HZ)) % 100);
+
+       free_page((unsigned long)str);
+done:
+       seq_printf(m, "\n\n");
+
+       return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+       /*
+        * Callback returns cpu-id to iterator for show routine, NULL to stop.
+        * However since NULL is also a valid cpu-id (0), we use a round-about
+        * way to pass it w/o having to kmalloc/free a 2 byte string.
+        * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
+        */
+       return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+       ++*pos;
+       return c_start(m, pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+       .start  = c_start,
+       .next   = c_next,
+       .stop   = c_stop,
+       .show   = show_cpuinfo
+};
+
+static DEFINE_PER_CPU(struct cpu, cpu_topology);
+
+static int __init topology_init(void)
+{
+       int cpu;
+
+       for_each_present_cpu(cpu)
+           register_cpu(&per_cpu(cpu_topology, cpu), cpu);
+
+       return 0;
+}
+
+subsys_initcall(topology_init);
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
new file mode 100644 (file)
index 0000000..63da347
--- /dev/null
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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/kernel.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/memblock.h>
+#ifdef CONFIG_BLOCK_DEV_RAM
+#include <linux/blk.h>
+#endif
+#include <linux/swap.h>
+#include <linux/module.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
+#include <asm/arcregs.h>
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
+char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
+EXPORT_SYMBOL(empty_zero_page);
+
+/* Default tot mem from .config */
+static unsigned long arc_mem_sz = CONFIG_ARC_PLAT_SDRAM_SIZE;
+
+/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
+static int __init setup_mem_sz(char *str)
+{
+       arc_mem_sz = memparse(str, NULL) & PAGE_MASK;
+
+       /* early console might not be setup yet - it will show up later */
+       pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(arc_mem_sz));
+
+       return 0;
+}
+early_param("mem", setup_mem_sz);
+
+/*
+ * First memory setup routine called from setup_arch()
+ * 1. setup swapper's mm @init_mm
+ * 2. Count the pages we have and setup bootmem allocator
+ * 3. zone setup
+ */
+void __init setup_arch_memory(void)
+{
+       unsigned long zones_size[MAX_NR_ZONES] = { 0, 0 };
+       unsigned long end_mem = CONFIG_LINUX_LINK_BASE + arc_mem_sz;
+
+       init_mm.start_code = (unsigned long)_text;
+       init_mm.end_code = (unsigned long)_etext;
+       init_mm.end_data = (unsigned long)_edata;
+       init_mm.brk = (unsigned long)_end;
+
+       /*
+        * We do it here, so that memory is correctly instantiated
+        * even if "mem=xxx" cmline over-ride is not given
+        */
+       memblock_add(CONFIG_LINUX_LINK_BASE, arc_mem_sz);
+
+       /*------------- externs in mm need setting up ---------------*/
+
+       /* first page of system - kernel .vector starts here */
+       min_low_pfn = PFN_DOWN(CONFIG_LINUX_LINK_BASE);
+
+       /* Last usable page of low mem (no HIGHMEM yet for ARC port) */
+       max_low_pfn = max_pfn = PFN_DOWN(end_mem);
+
+       max_mapnr = num_physpages = max_low_pfn - min_low_pfn;
+
+       /*------------- reserve kernel image -----------------------*/
+       memblock_reserve(CONFIG_LINUX_LINK_BASE,
+                        __pa(_end) - CONFIG_LINUX_LINK_BASE);
+
+       memblock_dump_all();
+
+       /*-------------- node setup --------------------------------*/
+       memset(zones_size, 0, sizeof(zones_size));
+       zones_size[ZONE_NORMAL] = num_physpages;
+
+       /*
+        * We can't use the helper free_area_init(zones[]) because it uses
+        * PAGE_OFFSET to compute the @min_low_pfn which would be wrong
+        * when our kernel doesn't start at PAGE_OFFSET, i.e.
+        * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE
+        */
+       free_area_init_node(0,                  /* node-id */
+                           zones_size,         /* num pages per zone */
+                           min_low_pfn,        /* first pfn of node */
+                           NULL);              /* NO holes */
+}
+
+/*
+ * mem_init - initializes memory
+ *
+ * Frees up bootmem
+ * Calculates and displays memory available/used
+ */
+void __init mem_init(void)
+{
+       int codesize, datasize, initsize, reserved_pages, free_pages;
+       int tmp;
+
+       high_memory = (void *)(CONFIG_LINUX_LINK_BASE + arc_mem_sz);
+
+       totalram_pages = free_all_bootmem();
+
+       /* count all reserved pages [kernel code/data/mem_map..] */
+       reserved_pages = 0;
+       for (tmp = 0; tmp < max_mapnr; tmp++)
+               if (PageReserved(mem_map + tmp))
+                       reserved_pages++;
+
+       /* XXX: nr_free_pages() is equivalent */
+       free_pages = max_mapnr - reserved_pages;
+
+       /*
+        * For the purpose of display below, split the "reserve mem"
+        * kernel code/data is already shown explicitly,
+        * Show any other reservations (mem_map[ ] et al)
+        */
+       reserved_pages -= (((unsigned int)_end - CONFIG_LINUX_LINK_BASE) >>
+                                                               PAGE_SHIFT);
+
+       codesize = _etext - _text;
+       datasize = _end - _etext;
+       initsize = __init_end - __init_begin;
+
+       pr_info("Memory Available: %dM / %ldM (%dK code, %dK data, %dK init, %dK reserv)\n",
+               PAGES_TO_MB(free_pages),
+               TO_MB(arc_mem_sz),
+               TO_KB(codesize), TO_KB(datasize), TO_KB(initsize),
+               PAGES_TO_KB(reserved_pages));
+}
+
+static void __init free_init_pages(const char *what, unsigned long begin,
+                                  unsigned long end)
+{
+       unsigned long addr;
+
+       pr_info("Freeing %s: %ldk [%lx] to [%lx]\n",
+               what, TO_KB(end - begin), begin, end);
+
+       /* need to check that the page we free is not a partial page */
+       for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) {
+               ClearPageReserved(virt_to_page(addr));
+               init_page_count(virt_to_page(addr));
+               free_page(addr);
+               totalram_pages++;
+       }
+}
+
+/*
+ * free_initmem: Free all the __init memory.
+ */
+void __init_refok free_initmem(void)
+{
+       free_init_pages("unused kernel memory",
+                       (unsigned long)__init_begin,
+                       (unsigned long)__init_end);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void __init free_initrd_mem(unsigned long start, unsigned long end)
+{
+       free_init_pages("initrd memory", start, end);
+}
+#endif
diff --git a/arch/arc/plat-arcfpga/platform.c b/arch/arc/plat-arcfpga/platform.c
new file mode 100644 (file)
index 0000000..7b5dcab
--- /dev/null
@@ -0,0 +1,29 @@
+/*
+ * ARC FPGA Platform support code
+ *
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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/types.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+
+/*
+ * Early Platform Initialization called from setup_arch()
+ */
+void __init arc_platform_early_init(void)
+{
+       pr_info("[plat-arcfpga]: registering early dev resources\n");
+}
+
+int __init fpga_plat_init(void)
+{
+       pr_info("[plat-arcfpga]: registering device resources\n");
+
+       return 0;
+}
+arch_initcall(fpga_plat_init);