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-rw-r--r--arch/riscv/kernel/head.S180
1 files changed, 109 insertions, 71 deletions
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 85f2073e7fe4..98a406474e7d 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -14,7 +14,7 @@
#include <asm/hwcap.h>
#include <asm/image.h>
-__INIT
+__HEAD
ENTRY(_start)
/*
* Image header expected by Linux boot-loaders. The image header data
@@ -45,8 +45,111 @@ ENTRY(_start)
.ascii RISCV_IMAGE_MAGIC2
.word 0
-.global _start_kernel
-_start_kernel:
+.align 2
+#ifdef CONFIG_MMU
+relocate:
+ /* Relocate return address */
+ li a1, PAGE_OFFSET
+ la a2, _start
+ sub a1, a1, a2
+ add ra, ra, a1
+
+ /* Point stvec to virtual address of intruction after satp write */
+ la a2, 1f
+ add a2, a2, a1
+ csrw CSR_TVEC, a2
+
+ /* Compute satp for kernel page tables, but don't load it yet */
+ srl a2, a0, PAGE_SHIFT
+ li a1, SATP_MODE
+ or a2, a2, a1
+
+ /*
+ * Load trampoline page directory, which will cause us to trap to
+ * stvec if VA != PA, or simply fall through if VA == PA. We need a
+ * full fence here because setup_vm() just wrote these PTEs and we need
+ * to ensure the new translations are in use.
+ */
+ la a0, trampoline_pg_dir
+ srl a0, a0, PAGE_SHIFT
+ or a0, a0, a1
+ sfence.vma
+ csrw CSR_SATP, a0
+.align 2
+1:
+ /* Set trap vector to spin forever to help debug */
+ la a0, .Lsecondary_park
+ csrw CSR_TVEC, a0
+
+ /* Reload the global pointer */
+.option push
+.option norelax
+ la gp, __global_pointer$
+.option pop
+
+ /*
+ * Switch to kernel page tables. A full fence is necessary in order to
+ * avoid using the trampoline translations, which are only correct for
+ * the first superpage. Fetching the fence is guarnteed to work
+ * because that first superpage is translated the same way.
+ */
+ csrw CSR_SATP, a2
+ sfence.vma
+
+ ret
+#endif /* CONFIG_MMU */
+#ifdef CONFIG_SMP
+ .global secondary_start_sbi
+secondary_start_sbi:
+ /* Mask all interrupts */
+ csrw CSR_IE, zero
+ csrw CSR_IP, zero
+
+ /* Load the global pointer */
+ .option push
+ .option norelax
+ la gp, __global_pointer$
+ .option pop
+
+ /*
+ * Disable FPU to detect illegal usage of
+ * floating point in kernel space
+ */
+ li t0, SR_FS
+ csrc CSR_STATUS, t0
+
+ /* Set trap vector to spin forever to help debug */
+ la a3, .Lsecondary_park
+ csrw CSR_TVEC, a3
+
+ slli a3, a0, LGREG
+ la a4, __cpu_up_stack_pointer
+ la a5, __cpu_up_task_pointer
+ add a4, a3, a4
+ add a5, a3, a5
+ REG_L sp, (a4)
+ REG_L tp, (a5)
+
+ .global secondary_start_common
+secondary_start_common:
+
+#ifdef CONFIG_MMU
+ /* Enable virtual memory and relocate to virtual address */
+ la a0, swapper_pg_dir
+ call relocate
+#endif
+ tail smp_callin
+#endif /* CONFIG_SMP */
+
+.Lsecondary_park:
+ /* We lack SMP support or have too many harts, so park this hart */
+ wfi
+ j .Lsecondary_park
+
+END(_start)
+
+ __INIT
+ENTRY(_start_kernel)
/* Mask all interrupts */
csrw CSR_IE, zero
csrw CSR_IP, zero
@@ -131,62 +234,10 @@ clear_bss_done:
call kasan_early_init
#endif
/* Start the kernel */
+ call soc_early_init
call parse_dtb
tail start_kernel
-#ifdef CONFIG_MMU
-relocate:
- /* Relocate return address */
- li a1, PAGE_OFFSET
- la a2, _start
- sub a1, a1, a2
- add ra, ra, a1
-
- /* Point stvec to virtual address of intruction after satp write */
- la a2, 1f
- add a2, a2, a1
- csrw CSR_TVEC, a2
-
- /* Compute satp for kernel page tables, but don't load it yet */
- srl a2, a0, PAGE_SHIFT
- li a1, SATP_MODE
- or a2, a2, a1
-
- /*
- * Load trampoline page directory, which will cause us to trap to
- * stvec if VA != PA, or simply fall through if VA == PA. We need a
- * full fence here because setup_vm() just wrote these PTEs and we need
- * to ensure the new translations are in use.
- */
- la a0, trampoline_pg_dir
- srl a0, a0, PAGE_SHIFT
- or a0, a0, a1
- sfence.vma
- csrw CSR_SATP, a0
-.align 2
-1:
- /* Set trap vector to spin forever to help debug */
- la a0, .Lsecondary_park
- csrw CSR_TVEC, a0
-
- /* Reload the global pointer */
-.option push
-.option norelax
- la gp, __global_pointer$
-.option pop
-
- /*
- * Switch to kernel page tables. A full fence is necessary in order to
- * avoid using the trampoline translations, which are only correct for
- * the first superpage. Fetching the fence is guarnteed to work
- * because that first superpage is translated the same way.
- */
- csrw CSR_SATP, a2
- sfence.vma
-
- ret
-#endif /* CONFIG_MMU */
-
.Lsecondary_start:
#ifdef CONFIG_SMP
/* Set trap vector to spin forever to help debug */
@@ -211,16 +262,10 @@ relocate:
beqz tp, .Lwait_for_cpu_up
fence
-#ifdef CONFIG_MMU
- /* Enable virtual memory and relocate to virtual address */
- la a0, swapper_pg_dir
- call relocate
+ tail secondary_start_common
#endif
- tail smp_callin
-#endif
-
-END(_start)
+END(_start_kernel)
#ifdef CONFIG_RISCV_M_MODE
ENTRY(reset_regs)
@@ -301,13 +346,6 @@ ENTRY(reset_regs)
END(reset_regs)
#endif /* CONFIG_RISCV_M_MODE */
-.section ".text", "ax",@progbits
-.align 2
-.Lsecondary_park:
- /* We lack SMP support or have too many harts, so park this hart */
- wfi
- j .Lsecondary_park
-
__PAGE_ALIGNED_BSS
/* Empty zero page */
.balign PAGE_SIZE