From: Greentime Hu <greent...@andestech.com> This patch includes the kernel startup code. It can get dtb pointer passed from bootloader. It will create a temp mapping by tlb instructions at beginning and goto start_kernel.
Signed-off-by: Vincent Chen <vince...@andestech.com> Signed-off-by: Greentime Hu <greent...@andestech.com> --- arch/nds32/kernel/head.S | 202 +++++++++++++++++++++++ arch/nds32/kernel/setup.c | 396 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 598 insertions(+) create mode 100644 arch/nds32/kernel/head.S create mode 100644 arch/nds32/kernel/setup.c diff --git a/arch/nds32/kernel/head.S b/arch/nds32/kernel/head.S new file mode 100644 index 0000000..fcd7922 --- /dev/null +++ b/arch/nds32/kernel/head.S @@ -0,0 +1,202 @@ +/* + * Copyright (C) 2005-2017 Andes Technology Corporation + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/ptrace.h> +#include <asm/asm-offsets.h> +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/l2_cache.h> +#include <asm/sizes.h> +#include <asm/thread_info.h> + +#ifdef CONFIG_CPU_BIG_ENDIAN +#define OF_DT_MAGIC 0xd00dfeed +#else +#define OF_DT_MAGIC 0xedfe0dd0 +#endif + + .globl swapper_pg_dir + .equ swapper_pg_dir, TEXTADDR - 0x4000 + +/* + * Kernel startup entry point. + */ + .section ".head.text", "ax" + .type _stext, %function +ENTRY(_stext) + setgie.d ! Disable interrupt + isb +/* + * Disable I/D-cache and enable it at a proper time + */ + mfsr $r0, $mr8 + li $r1, #~(CACHE_CTL_mskIC_EN|CACHE_CTL_mskDC_EN) + and $r0, $r0, $r1 + mtsr $r0, $mr8 + +/* + * Process device tree blob + */ + andi $r0,$r2,#0x3 + li $r10, 0 + bne $r0, $r10, _nodtb + lwi $r0, [$r2] + li $r1, OF_DT_MAGIC + bne $r0, $r1, _nodtb + move $r10, $r2 +_nodtb: + +/* + * Create a temporary mapping area for booting, before start_kernel + */ + sethi $r4, hi20(swapper_pg_dir) + li $p0, (PAGE_OFFSET - PHYS_OFFSET) + sub $r4, $r4, $p0 + tlbop FlushAll ! invalidate TLB\n" + isb + mtsr $r4, $L1_PPTB ! load page table pointer\n" + +/* set NTC0 cacheable/writeback, mutliple page size in use */ + mfsr $r3, $MMU_CTL + li $r0, #~MMU_CTL_mskNTC0 + and $r3, $r3, $r0 +#ifdef CONFIG_ANDES_PAGE_SIZE_4KB + ori $r3, $r3, #(MMU_CTL_mskMPZIU|(MMU_CTL_CACHEABLE_WB << MMU_CTL_offNTC0)) +#else + ori $r3, $r3, #(MMU_CTL_mskMPZIU|(MMU_CTL_CACHEABLE_WB << MMU_CTL_offNTC0)|MMU_CTL_D8KB) +#endif +#ifdef CONFIG_HW_SUPPORT_UNALIGNMENT_ACCESS + li $r0, #MMU_CTL_UNA + or $r3, $r3, $r0 +#endif + mtsr $r3, $MMU_CTL + isb + +/* set page size and size of kernel image */ + mfsr $r0, $MMU_CFG + srli $r3, $r0, MMU_CFG_offfEPSZ + zeb $r3, $r3 + bnez $r3, _extra_page_size_support +#ifdef CONFIG_ANDES_PAGE_SIZE_4KB + li $r5, #SZ_4K ! Use 4KB page size +#else + li $r5, #SZ_8K ! Use 8KB page size + li $r3, #1 +#endif + mtsr $r3, $TLB_MISC + b _image_size_check + +_extra_page_size_support: ! Use epzs pages size + clz $r6, $r3 + subri $r2, $r6, #31 + li $r3, #1 + sll $r3, $r3, $r2 + /* MMU_CFG.EPSZ value -> meaning */ + mul $r5, $r3, $r3 + slli $r5, $r5, #14 + /* MMU_CFG.EPSZ -> TLB_MISC.ACC_PSZ */ + addi $r3, $r2, #0x2 + mtsr $r3, $TLB_MISC + +_image_size_check: + /* calculate the image maximum size accepted by TLB config */ + andi $r6, $r0, MMU_CFG_mskTBW + andi $r0, $r0, MMU_CFG_mskTBS + srli $r6, $r6, MMU_CFG_offTBW + srli $r0, $r0, MMU_CFG_offTBS + /* + * we just map the kernel to the maximum way - 1 of tlb + * reserver one way for UART VA mapping + * it will cause page fault if UART mapping cover the kernel mapping + * + * direct mapping is not supported now. + */ + li $r2, 't' + beqz $r6, __error ! MMU_CFG.TBW = 0 is direct mappin + addi $r0, $r0, #0x2 ! MMU_CFG.TBS value -> meaning + sll $r0, $r6, $r0 ! entries = k-way * n-set + mul $r6, $r0, $r5 ! max size = entries * page size + /* check kernel image size */ + la $r3, (_end - PAGE_OFFSET) + li $r2, 's' + bgt $r3, $r6, __error + + li $r2, #(PHYS_OFFSET + TLB_DATA_kernel_text_attr) + li $r3, PAGE_OFFSET + add $r6, $r6, $r3 + +_tlb: + mtsr $r3, $TLB_VPN + dsb + tlbop $r2, RWR + isb + add $r3, $r3, $r5 + add $r2, $r2, $r5 + bgt $r6, $r3, _tlb + mfsr $r3, $TLB_MISC ! setup access page size + li $r2, #~0xf + and $r3, $r3, $r2 +#ifdef CONFIG_ANDES_PAGE_SIZE_8KB + ori $r3, $r3, #0x1 +#endif + mtsr $r3, $TLB_MISC + + mfsr $r0, $MISC_CTL ! Enable BTB and RTP and shadow sp + ori $r0, $r0, #MISC_init + mtsr $r0, $MISC_CTL + + mfsr $p1, $PSW + li $r15, #~PSW_clr ! clear WBNA|DME|IME|DT|IT|POM|INTL|GIE + and $p1, $p1, $r15 + ori $p1, $p1, #PSW_init + mtsr $p1, $IPSW ! when iret, it will automatically enable MMU + la $lp, __mmap_switched + mtsr $lp, $IPC + iret + nop + + .type __switch_data, %object +__switch_data: + .long __bss_start ! $r6 + .long _end ! $r7 + .long __atags_pointer ! $atag_pointer + .long init_task ! $r9, move to $r25 + .long init_thread_union + THREAD_SIZE ! $sp + + +/* + * The following fragment of code is executed with the MMU on in MMU mode, + * and uses absolute addresses; this is not position independent. + */ + .align + .type __mmap_switched, %function +__mmap_switched: + la $r3, __switch_data + lmw.bim $r6, [$r3], $r9, #0b0001 + move $r25, $r9 + move $fp, #0 ! Clear BSS (and zero $fp) + beq $r7, $r6, _RRT +1: swi.bi $fp, [$r6], #4 + bne $r7, $r6, 1b + swi $r10, [$r8] + +_RRT: + b start_kernel + +__error: + b __error diff --git a/arch/nds32/kernel/setup.c b/arch/nds32/kernel/setup.c new file mode 100644 index 0000000..58bb0f9 --- /dev/null +++ b/arch/nds32/kernel/setup.c @@ -0,0 +1,396 @@ +/* + * Copyright (C) 2005-2017 Andes Technology Corporation + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/cpu.h> +#include <linux/bootmem.h> +#include <linux/seq_file.h> +#include <linux/memblock.h> +#include <linux/console.h> +#include <linux/screen_info.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/of_fdt.h> +#include <linux/of_platform.h> +#include <asm/setup.h> +#include <asm/sections.h> +#include <asm/proc-fns.h> +#include <asm/cache_info.h> +#include <asm/elf.h> +#include <nds32_intrinsic.h> + +#define HWCAP_MFUSR_PC 0x000001 +#define HWCAP_EXT 0x000002 +#define HWCAP_EXT2 0x000004 +#define HWCAP_FPU 0x000008 +#define HWCAP_AUDIO 0x000010 +#define HWCAP_BASE16 0x000020 +#define HWCAP_STRING 0x000040 +#define HWCAP_REDUCED_REGS 0x000080 +#define HWCAP_VIDEO 0x000100 +#define HWCAP_ENCRYPT 0x000200 +#define HWCAP_EDM 0x000400 +#define HWCAP_LMDMA 0x000800 +#define HWCAP_PFM 0x001000 +#define HWCAP_HSMP 0x002000 +#define HWCAP_TRACE 0x004000 +#define HWCAP_DIV 0x008000 +#define HWCAP_MAC 0x010000 +#define HWCAP_L2C 0x020000 +#define HWCAP_FPU_DP 0x040000 +#define HWCAP_V2 0x080000 +#define HWCAP_DX_REGS 0x100000 + +extern struct mm_struct init_mm; +unsigned long cpu_id, cpu_rev, cpu_cfgid; +char cpu_series; +char *endianness = NULL; + +unsigned int __atags_pointer __initdata; +unsigned int elf_hwcap; +EXPORT_SYMBOL(elf_hwcap); + +extern void __init early_init_devtree(void *params); +extern void __init early_trap_init(void); +/* + * The following string table, must sync with HWCAP_xx bitmask, + * which is defined in <asm/procinfo.h> + */ +static const char *hwcap_str[] = { + "mfusr_pc", + "perf1", + "perf2", + "fpu", + "audio", + "16b", + "string", + "reduced_regs", + "video", + "encrypt", + "edm", + "lmdma", + "pfm", + "hsmp", + "trace", + "div", + "mac", + "l2c", + "dx_regs", + "v2", + NULL, +}; + +#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH +#define WRITE_METHOD "write through" +#else +#define WRITE_METHOD "write back" +#endif + +struct cache_info L1_cache_info[2]; +static void __init dump_cpu_info(int cpu) +{ + int i, p = 0; + char str[sizeof(hwcap_str) + 16]; + + for (i = 0; hwcap_str[i]; i++) { + if (elf_hwcap & (1 << i)) { + sprintf(str + p, "%s ", hwcap_str[i]); + p += strlen(hwcap_str[i]) + 1; + } + } + + pr_info("CPU%d Featuretures: %s\n", cpu, str); + + L1_cache_info[ICACHE].ways = CACHE_WAY(ICACHE); + L1_cache_info[ICACHE].line_size = CACHE_LINE_SIZE(ICACHE); + L1_cache_info[ICACHE].sets = CACHE_SET(ICACHE); + L1_cache_info[ICACHE].size = + L1_cache_info[ICACHE].ways * L1_cache_info[ICACHE].line_size * + L1_cache_info[ICACHE].sets / 1024; + pr_info("L1I:%dKB/%dS/%dW/%dB\n", L1_cache_info[ICACHE].size, + L1_cache_info[ICACHE].sets, L1_cache_info[ICACHE].ways, + L1_cache_info[ICACHE].line_size); + L1_cache_info[DCACHE].ways = CACHE_WAY(DCACHE); + L1_cache_info[DCACHE].line_size = CACHE_LINE_SIZE(DCACHE); + L1_cache_info[DCACHE].sets = CACHE_SET(DCACHE); + L1_cache_info[DCACHE].size = + L1_cache_info[DCACHE].ways * L1_cache_info[DCACHE].line_size * + L1_cache_info[DCACHE].sets / 1024; + pr_info("L1D:%dKB/%dS/%dW/%dB\n", L1_cache_info[DCACHE].size, + L1_cache_info[DCACHE].sets, L1_cache_info[DCACHE].ways, + L1_cache_info[DCACHE].line_size); + pr_info("L1 D-Cache is %s\n", WRITE_METHOD); + if (L1_cache_info[DCACHE].size != L1_CACHE_BYTES) + pr_crit + ("The cache line size(%d) of this processor is not the same as L1_CACHE_BYTES(%d).\n", + L1_cache_info[DCACHE].size, L1_CACHE_BYTES); +#ifdef CONFIG_CPU_CACHE_ALIASING + { + int aliasing_num; + aliasing_num = + L1_cache_info[ICACHE].size * 1024 / PAGE_SIZE / + L1_cache_info[ICACHE].ways; + L1_cache_info[ICACHE].aliasing_num = aliasing_num; + L1_cache_info[ICACHE].aliasing_mask = + (aliasing_num - 1) << PAGE_SHIFT; + aliasing_num = + L1_cache_info[DCACHE].size * 1024 / PAGE_SIZE / + L1_cache_info[DCACHE].ways; + L1_cache_info[DCACHE].aliasing_num = aliasing_num; + L1_cache_info[DCACHE].aliasing_mask = + (aliasing_num - 1) << PAGE_SHIFT; + } +#endif +} + +static void __init setup_cpuinfo(void) +{ + unsigned long tmp = 0, cpu_name; + + cpu_dcache_inval_all(); + cpu_icache_inval_all(); + __nds32__isb(); + + cpu_id = (__nds32__mfsr(NDS32_SR_CPU_VER) & CPU_VER_mskCPUID) >> CPU_VER_offCPUID; + cpu_name = ((cpu_id) & 0xf0) >> 4; + cpu_series = cpu_name ? cpu_name - 10 + 'A' : 'N'; + cpu_id = cpu_id & 0xf; + cpu_rev = (__nds32__mfsr(NDS32_SR_CPU_VER) & CPU_VER_mskREV) >> CPU_VER_offREV; + cpu_cfgid = (__nds32__mfsr(NDS32_SR_CPU_VER) & CPU_VER_mskCFGID) >> CPU_VER_offCFGID; + + pr_info("CPU:%c%ld, CPU_VER 0x%08x(id %lu, rev %lu, cfg %lu)\n", + cpu_series, cpu_id, __nds32__mfsr(NDS32_SR_CPU_VER), cpu_id, cpu_rev, cpu_cfgid); + + elf_hwcap |= HWCAP_MFUSR_PC; + + if (((__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskBASEV) >> MSC_CFG_offBASEV) == 0) { + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskDIV) + elf_hwcap |= HWCAP_DIV; + + if ((__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskMAC) + || (cpu_id == 12 && cpu_rev < 4)) + elf_hwcap |= HWCAP_MAC; + } else { + elf_hwcap |= HWCAP_V2; + elf_hwcap |= HWCAP_DIV; + elf_hwcap |= HWCAP_MAC; + } + + if (cpu_cfgid & 0x0001) + elf_hwcap |= HWCAP_EXT; + + if (cpu_cfgid & 0x0002) + elf_hwcap |= HWCAP_BASE16; + + if (cpu_cfgid & 0x0004) + elf_hwcap |= HWCAP_EXT2; + + if (cpu_cfgid & 0x0008) + elf_hwcap |= HWCAP_FPU; + + if (cpu_cfgid & 0x0010) + elf_hwcap |= HWCAP_STRING; + + if (__nds32__mfsr(NDS32_SR_MMU_CFG) & MMU_CFG_mskDE) + endianness = "MSB"; + else + endianness = "LSB"; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskEDM) + elf_hwcap |= HWCAP_EDM; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskLMDMA) + elf_hwcap |= HWCAP_LMDMA; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskPFM) + elf_hwcap |= HWCAP_PFM; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskHSMP) + elf_hwcap |= HWCAP_HSMP; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskTRACE) + elf_hwcap |= HWCAP_TRACE; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskAUDIO) + elf_hwcap |= HWCAP_AUDIO; + + if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskL2C) + elf_hwcap |= HWCAP_L2C; + + tmp = __nds32__mfsr(NDS32_SR_CACHE_CTL); + if (!IS_ENABLED(CONFIG_CPU_DCACHE_DISABLE)) + tmp |= CACHE_CTL_mskDC_EN; + + if (!IS_ENABLED(CONFIG_CPU_ICACHE_DISABLE)) + tmp |= CACHE_CTL_mskIC_EN; + __nds32__mtsr_isb(tmp, NDS32_SR_CACHE_CTL); + + dump_cpu_info(smp_processor_id()); +} + +static void __init setup_memory(void) +{ + unsigned long ram_start_pfn; + unsigned long free_ram_start_pfn; + phys_addr_t memory_start, memory_end; + struct memblock_region *region; + + memory_end = memory_start = 0; + + /* Find main memory where is the kernel */ + for_each_memblock(memory, region) { + memory_start = region->base; + memory_end = region->base + region->size; + pr_info("%s: Memory: 0x%x-0x%x\n", __func__, + memory_start, memory_end); + } + + if (!memory_end) { + panic("No memory!"); + } + + ram_start_pfn = PFN_UP(memblock_start_of_DRAM()); + /* free_ram_start_pfn is first page after kernel */ + free_ram_start_pfn = PFN_UP(__pa(&_end)); + max_pfn = PFN_DOWN(memblock_end_of_DRAM()); + /* it could update max_pfn */ + if (max_pfn - ram_start_pfn <= MAXMEM_PFN) + max_low_pfn = max_pfn; + else { + max_low_pfn = MAXMEM_PFN + ram_start_pfn; + if (!IS_ENABLED(CONFIG_HIGHMEM)) + max_pfn = MAXMEM_PFN + ram_start_pfn; + } + /* high_memory is related with VMALLOC */ + high_memory = (void *)__va(max_low_pfn * PAGE_SIZE); + min_low_pfn = free_ram_start_pfn; + + /* + * initialize the boot-time allocator (with low memory only). + * + * This makes the memory from the end of the kernel to the end of + * RAM usable. + */ + memblock_set_bottom_up(true); + memblock_reserve(PFN_PHYS(ram_start_pfn), PFN_PHYS(free_ram_start_pfn - ram_start_pfn)); + + early_init_fdt_reserve_self(); + early_init_fdt_scan_reserved_mem(); + + memblock_dump_all(); +} + +void __init setup_arch(char **cmdline_p) +{ + early_init_devtree(__atags_pointer ? + phys_to_virt(__atags_pointer) : __dtb_start); + + setup_cpuinfo(); + + 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; + + /* setup bootmem allocator */ + setup_memory(); + + /* paging_init() sets up the MMU and marks all pages as reserved */ + paging_init(); + + /* use generic way to parse */ + parse_early_param(); + + unflatten_and_copy_device_tree(); + + if(IS_ENABLED(CONFIG_VT)) { + if(IS_ENABLED(CONFIG_VGA_CONSOLE)) + conswitchp = &vga_con; + else if(IS_ENABLED(CONFIG_DUMMY_CONSOLE)) + conswitchp = &dummy_con; + } + + *cmdline_p = boot_command_line; + early_trap_init(); +} + +void calibrate_delay(void) +{ + const int *val; + struct device_node *cpu = NULL; + cpu = of_find_compatible_node(NULL, NULL, "andestech,n13"); + val = of_get_property(cpu, "clock-frequency", NULL); + if (!val) + panic("no cpu 'clock-frequency' parameter in device tree"); + loops_per_jiffy = *val / HZ; + pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n", + loops_per_jiffy / (500000 / HZ), + (loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy); +} + +static int c_show(struct seq_file *m, void *v) +{ + int i; + + seq_printf(m, "Processor\t: %c%ld (id %lu, rev %lu, cfg %lu)\n", + cpu_series, cpu_id, cpu_id, cpu_rev, cpu_cfgid); + + seq_printf(m, "L1I\t\t: %luKB/%luS/%luW/%luB\n", + CACHE_SET(ICACHE) * CACHE_WAY(ICACHE) * + CACHE_LINE_SIZE(ICACHE) / 1024, CACHE_SET(ICACHE), + CACHE_WAY(ICACHE), CACHE_LINE_SIZE(ICACHE)); + + seq_printf(m, "L1D\t\t: %luKB/%luS/%luW/%luB\n", + CACHE_SET(DCACHE) * CACHE_WAY(DCACHE) * + CACHE_LINE_SIZE(DCACHE) / 1024, CACHE_SET(DCACHE), + CACHE_WAY(DCACHE), CACHE_LINE_SIZE(DCACHE)); + + seq_printf(m, "BogoMIPS\t: %lu.%02lu\n", + loops_per_jiffy / (500000 / HZ), + (loops_per_jiffy / (5000 / HZ)) % 100); + + /* dump out the processor features */ + seq_puts(m, "Features\t: "); + + for (i = 0; hwcap_str[i]; i++) + if (elf_hwcap & (1 << i)) + seq_printf(m, "%s ", hwcap_str[i]); + + seq_puts(m, "\n\n"); + + return 0; +} + +static void *c_start(struct seq_file *m, loff_t * pos) +{ + return *pos < 1 ? (void *)1 : NULL; +} + +static void *c_next(struct seq_file *m, void *v, loff_t * pos) +{ + ++*pos; + return NULL; +} + +static void c_stop(struct seq_file *m, void *v) +{ +} + +struct seq_operations cpuinfo_op = { + .start = c_start, + .next = c_next, + .stop = c_stop, + .show = c_show +}; -- 1.7.9.5
