[PATCH V5 03/30] csky: Kernel booting

Guo Ren
2018-09-24T14:38:08Z

This patch add boot code. Thx boot params is all in dtb and it's
the only way to let kernel get bootloader param information.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
---
arch/csky/kernel/head.S | 78 +++++++++++++++++++++
arch/csky/kernel/setup.c | 151 +++++++++++++++++++++++++++++++++++++++++
arch/csky/kernel/vmlinux.lds.S | 64 +++++++++++++++++
3 files changed, 293 insertions(+)
create mode 100644 arch/csky/kernel/head.S
create mode 100644 arch/csky/kernel/setup.c
create mode 100644 arch/csky/kernel/vmlinux.lds.S

diff --git a/arch/csky/kernel/head.S b/arch/csky/kernel/head.S
new file mode 100644
index 0000000..80bb9c6
--- /dev/null
+++ b/arch/csky/kernel/head.S
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/page.h>
+#include <abi/entry.h>
+
+__HEAD
+ENTRY(_start)
+ /* set super user mode */
+ lrw a3, DEFAULT_PSR_VALUE
+ mtcr a3, psr
+ psrset ee
+
+ SETUP_MMU a3
+
+ /* set stack point */
+ lrw a3, init_thread_union + THREAD_SIZE
+ mov sp, a3
+
+ jmpi csky_start
+END(_start)
+
+#ifdef CONFIG_SMP
+.align 10
+ENTRY(_start_smp_secondary)
+ /* Invalid I/Dcache BTB BHT */
+ movi a3, 7
+ lsli a3, 16
+ addi a3, (1<<4) | 3
+ mtcr a3, cr17
+
+ tlbi.alls
+
+ /* setup PAGEMASK */
+ movi a3, 0
+ mtcr a3, cr<6, 15>
+
+ /* setup MEL0/MEL1 */
+ grs a0, _start_smp_pc
+_start_smp_pc:
+ bmaski a1, 13
+ andn a0, a1
+ movi a1, 0x00000006
+ movi a2, 0x00001006
+ or a1, a0
+ or a2, a0
+ mtcr a1, cr<2, 15>
+ mtcr a2, cr<3, 15>
+
+ /* setup MEH */
+ mtcr a0, cr<4, 15>
+
+ /* write TLB */
+ bgeni a3, 28
+ mtcr a3, cr<8, 15>
+
+ SETUP_MMU a3
+
+ /* enable MMU */
+ movi a3, 1
+ mtcr a3, cr18
+
+ jmpi _goto_mmu_on
+_goto_mmu_on:
+ lrw a3, DEFAULT_PSR_VALUE
+ mtcr a3, psr
+ psrset ee
+
+ /* set stack point */
+ lrw a3, secondary_stack
+ ld.w a3, (a3, 0)
+ mov sp, a3
+
+ jmpi csky_start_secondary
+END(_start_smp_secondary)
+#endif
diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c
new file mode 100644
index 0000000..27f9e10
--- /dev/null
+++ b/arch/csky/kernel/setup.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/console.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h>
+#include <linux/initrd.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/start_kernel.h>
+#include <linux/dma-contiguous.h>
+#include <asm/sections.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+
+phys_addr_t __init_memblock memblock_end_of_REG0(void)
+{
+ return (memblock.memory.regions[0].base + memblock.memory.regions[0].size);
+}
+
+phys_addr_t __init_memblock memblock_start_of_REG1(void)
+{
+ return memblock.memory.regions[1].base;
+}
+
+size_t __init_memblock memblock_size_of_REG1(void)
+{
+ return memblock.memory.regions[1].size;
+}
+
+static void __init csky_memblock_init(void)
+{
+ unsigned long zone_size[MAX_NR_ZONES];
+ unsigned long zhole_size[MAX_NR_ZONES];
+ signed long size;
+
+ memblock_reserve(__pa(_stext), _end - _stext);
+#ifdef CONFIG_BLK_DEV_INITRD
+ memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
+#endif
+
+ early_init_fdt_reserve_self();
+ early_init_fdt_scan_reserved_mem();
+
+ memblock_dump_all();
+
+ memset(zone_size, 0, sizeof(zone_size));
+ memset(zhole_size, 0, sizeof(zhole_size));
+
+ min_low_pfn = PFN_UP(memblock_start_of_DRAM());
+ max_pfn = PFN_DOWN(memblock_end_of_DRAM());
+
+ max_low_pfn = PFN_UP(memblock_end_of_REG0());
+ if (max_low_pfn == 0)
+ max_low_pfn = max_pfn;
+
+ size = max_pfn - min_low_pfn;
+
+ if (memblock.memory.cnt > 1) {
+ zone_size[ZONE_NORMAL] = PFN_DOWN(memblock_start_of_REG1()) - min_low_pfn;
+ zhole_size[ZONE_NORMAL] = PFN_DOWN(memblock_start_of_REG1()) - max_low_pfn;
+ } else {
+ if (size <= PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET))
+ zone_size[ZONE_NORMAL] = max_pfn - min_low_pfn;
+ else {
+ zone_size[ZONE_NORMAL] = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
+ max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
+ }
+ }
+
+#ifdef CONFIG_HIGHMEM
+ size = 0;
+ if(memblock.memory.cnt > 1) {
+ size = PFN_DOWN(memblock_size_of_REG1());
+ highstart_pfn = PFN_DOWN(memblock_start_of_REG1());
+ } else {
+ size = max_pfn - min_low_pfn - PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
+ highstart_pfn = min_low_pfn + PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
+ }
+
+ if (size > 0)
+ zone_size[ZONE_HIGHMEM] = size;
+
+ highend_pfn = max_pfn;
+#endif
+ memblock_set_current_limit(PFN_PHYS(max_low_pfn));
+
+ dma_contiguous_reserve(0);
+
+ free_area_init_node(0, zone_size, min_low_pfn, zhole_size);
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+ *cmdline_p = boot_command_line;
+
+ console_verbose();
+
+ pr_info("C-SKY: https://github.com/c-sky/csky-linux\n");
+ pr_info("Phys. mem: %ldMB\n", (unsigned long) memblock_phys_mem_size()/1024/1024);
+
+ init_mm.start_code = (unsigned long) _stext;
+ init_mm.end_code = (unsigned long) _etext;
+ init_mm.end_data = (unsigned long) _edata;
+ init_mm.brk = (unsigned long) _end;
+
+ parse_early_param();
+
+ csky_memblock_init();
+
+ unflatten_and_copy_device_tree();
+
+#ifdef CONFIG_SMP
+ setup_smp();
+#endif
+
+ sparse_init();
+
+#ifdef CONFIG_HIGHMEM
+ kmap_init();
+#endif
+
+#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
+ conswitchp = &dummy_con;
+#endif
+}
+
+extern void pre_trap_init(void);
+extern void pre_mmu_init(void);
+
+asmlinkage __visible void __init csky_start(
+ unsigned int unused,
+ void * param
+ )
+{
+ /* Clean up bss section */
+ memset(__bss_start, 0, __bss_stop - __bss_start);
+
+ pre_trap_init();
+ pre_mmu_init();
+
+#ifdef CONFIG_CSKY_BUILTIN_DTB
+ pr_info("Use builtin dtb\n");
+ early_init_dt_scan(__dtb_start);
+#else
+ early_init_dt_scan(param);
+#endif
+ start_kernel();
+
+ while(1);
+}
diff --git a/arch/csky/kernel/vmlinux.lds.S b/arch/csky/kernel/vmlinux.lds.S
new file mode 100644
index 0000000..0c019b5
--- /dev/null
+++ b/arch/csky/kernel/vmlinux.lds.S
@@ -0,0 +1,64 @@
+#include <asm/vmlinux.lds.h>
+#include <asm/page.h>
+
+OUTPUT_ARCH(csky)
+ENTRY(_start)
+
+#ifndef __cskyBE__
+jiffies = jiffies_64;
+#else
+jiffies = jiffies_64 + 4;
+#endif
+
+#define VBR_BASE \
+ . = ALIGN(1024); \
+ vec_base = .; \
+ . += 512;
+
+SECTIONS
+{
+ . = PAGE_OFFSET + PHYS_OFFSET_OFFSET;
+
+ _stext = .;
+ __init_begin = .;
+ HEAD_TEXT_SECTION
+ INIT_TEXT_SECTION(PAGE_SIZE)
+ INIT_DATA_SECTION(PAGE_SIZE)
+ PERCPU_SECTION(L1_CACHE_BYTES)
+ . = ALIGN(PAGE_SIZE);
+ __init_end = .;
+
+ .text : AT(ADDR(.text) - LOAD_OFFSET) {
+ _text = .;
+ IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
+ TEXT_TEXT
+ SCHED_TEXT
+ CPUIDLE_TEXT
+ LOCK_TEXT
+ KPROBES_TEXT
+ *(.fixup)
+ *(.gnu.warning)
+ } = 0
+ _etext = .;
+
+ /* __init_begin __init_end must be page aligned for free_initmem */
+ . = ALIGN(PAGE_SIZE);
+
+
+ _sdata = .;
+ RO_DATA_SECTION(PAGE_SIZE)
+ RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+ _edata = .;
+
+ NOTES
+ EXCEPTION_TABLE(L1_CACHE_BYTES)
+ BSS_SECTION(L1_CACHE_BYTES, PAGE_SIZE, L1_CACHE_BYTES)
+ VBR_BASE
+ _end = . ;
+
+ STABS_DEBUG
+ DWARF_DEBUG
+
+ DISCARDS
+}
--
2.7.4