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-rw-r--r--arch/csky/kernel/setup.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c
new file mode 100644
index 000000000000..e0d6ca86ea8c
--- /dev/null
+++ b/arch/csky/kernel/setup.c
@@ -0,0 +1,165 @@
+// 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/initrd.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/start_kernel.h>
+#include <linux/dma-map-ops.h>
+#include <asm/sections.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+
+#ifdef CONFIG_BLK_DEV_INITRD
+static void __init setup_initrd(void)
+{
+ unsigned long size;
+
+ if (initrd_start >= initrd_end) {
+ pr_err("initrd not found or empty");
+ goto disable;
+ }
+
+ if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
+ pr_err("initrd extends beyond end of memory");
+ goto disable;
+ }
+
+ size = initrd_end - initrd_start;
+
+ if (memblock_is_region_reserved(__pa(initrd_start), size)) {
+ pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region",
+ __pa(initrd_start), size);
+ goto disable;
+ }
+
+ memblock_reserve(__pa(initrd_start), size);
+
+ pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
+ (void *)(initrd_start), size);
+
+ initrd_below_start_ok = 1;
+
+ return;
+
+disable:
+ initrd_start = initrd_end = 0;
+
+ pr_err(" - disabling initrd\n");
+}
+#endif
+
+static void __init csky_memblock_init(void)
+{
+ unsigned long lowmem_size = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
+ unsigned long sseg_size = PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET);
+ unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
+ signed long size;
+
+ memblock_reserve(__pa(_start), _end - _start);
+
+ early_init_fdt_reserve_self();
+ early_init_fdt_scan_reserved_mem();
+
+ memblock_dump_all();
+
+ min_low_pfn = PFN_UP(memblock_start_of_DRAM());
+ max_low_pfn = max_pfn = PFN_DOWN(memblock_end_of_DRAM());
+
+ size = max_pfn - min_low_pfn;
+
+ if (size >= lowmem_size) {
+ max_low_pfn = min_low_pfn + lowmem_size;
+#ifdef CONFIG_PAGE_OFFSET_80000000
+ write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE);
+#endif
+ } else if (size > sseg_size) {
+ max_low_pfn = min_low_pfn + sseg_size;
+ }
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ setup_initrd();
+#endif
+
+ max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
+
+ mmu_init(min_low_pfn, max_low_pfn);
+
+#ifdef CONFIG_HIGHMEM
+ max_zone_pfn[ZONE_HIGHMEM] = max_pfn;
+
+ highstart_pfn = max_low_pfn;
+ highend_pfn = max_pfn;
+#endif
+ memblock_set_current_limit(PFN_PHYS(max_low_pfn));
+
+ dma_contiguous_reserve(0);
+
+ free_area_init(max_zone_pfn);
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+ *cmdline_p = boot_command_line;
+
+ console_verbose();
+
+ pr_info("Phys. mem: %ldMB\n",
+ (unsigned long) memblock_phys_mem_size()/1024/1024);
+
+ setup_initial_init_mm(_start, _etext, _edata, _end);
+
+ parse_early_param();
+
+ csky_memblock_init();
+
+ unflatten_and_copy_device_tree();
+
+#ifdef CONFIG_SMP
+ setup_smp();
+#endif
+
+ sparse_init();
+
+ fixaddr_init();
+
+#ifdef CONFIG_HIGHMEM
+ kmap_init();
+#endif
+}
+
+unsigned long va_pa_offset;
+EXPORT_SYMBOL(va_pa_offset);
+
+static inline unsigned long read_mmu_msa(void)
+{
+#ifdef CONFIG_PAGE_OFFSET_80000000
+ return read_mmu_msa0();
+#endif
+
+#ifdef CONFIG_PAGE_OFFSET_A0000000
+ return read_mmu_msa1();
+#endif
+}
+
+asmlinkage __visible void __init csky_start(unsigned int unused,
+ void *dtb_start)
+{
+ /* Clean up bss section */
+ memset(__bss_start, 0, __bss_stop - __bss_start);
+
+ va_pa_offset = read_mmu_msa() & ~(SSEG_SIZE - 1);
+
+ pre_trap_init();
+
+ if (dtb_start == NULL)
+ early_init_dt_scan(__dtb_start, __pa(dtb_start));
+ else
+ early_init_dt_scan(dtb_start, __pa(dtb_start));
+
+ start_kernel();
+
+ asm volatile("br .\n");
+}