X-Git-Url: http://git.monstr.eu/?a=blobdiff_plain;f=arch%2Friscv%2Fkernel%2Fhead.S;h=173507395a6bb5568d75097a8d936cec2ad70ad8;hb=e011995e826f85fbe55dc7d4ce649461163d1052;hp=271860fc2c3f02a5d50552339a005004444ab456;hpb=332008256f1f7cd8294acd6e288fb821f685d1a9;p=linux-2.6-microblaze.git

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 271860fc2c3f..173507395a6b 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 +45,85 @@ 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
+	/* Set trap vector to spin forever to help debug */
+	la a3, .Lsecondary_park
+	csrw CSR_TVEC, a3
+
+	slli a3, a0, LGREG
+	.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
@@ -58,6 +135,12 @@ _start_kernel:
 	/* Reset all registers except ra, a0, a1 */
 	call reset_regs
 
+	/* Setup a PMP to permit access to all of memory. */
+	li a0, -1
+	csrw CSR_PMPADDR0, a0
+	li a0, (PMP_A_NAPOT | PMP_R | PMP_W | PMP_X)
+	csrw CSR_PMPCFG0, a0
+
 	/*
 	 * The hartid in a0 is expected later on, and we have no firmware
 	 * to hand it to us.
@@ -128,59 +211,6 @@ clear_bss_done:
 	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 */
@@ -205,16 +235,10 @@ 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)
@@ -295,13 +319,6 @@ 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