X-Git-Url: http://git.monstr.eu/?a=blobdiff_plain;f=arch%2Friscv%2Flib%2Fuaccess.S;h=63bc691cff91b275100a8339f1cc387555e79ae0;hb=d842bc6c0579ca7643eed029beabab3ac562a335;hp=bceb0629e440eb63e604b6a09f5338ce1b2d2e11;hpb=8b9cc17a46215af733c83bea36366419133dfa09;p=linux-2.6-microblaze.git

diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
index bceb0629e440..63bc691cff91 100644
--- a/arch/riscv/lib/uaccess.S
+++ b/arch/riscv/lib/uaccess.S
@@ -30,23 +30,23 @@ ENTRY(__asm_copy_from_user)
 	 * t0 - end of uncopied dst
 	 */
 	add	t0, a0, a2
-	bgtu	a0, t0, 5f
 
 	/*
 	 * Use byte copy only if too small.
+	 * SZREG holds 4 for RV32 and 8 for RV64
 	 */
-	li	a3, 8*SZREG /* size must be larger than size in word_copy */
+	li	a3, 9*SZREG /* size must be larger than size in word_copy */
 	bltu	a2, a3, .Lbyte_copy_tail
 
 	/*
-	 * Copy first bytes until dst is align to word boundary.
+	 * Copy first bytes until dst is aligned to word boundary.
 	 * a0 - start of dst
 	 * t1 - start of aligned dst
 	 */
 	addi	t1, a0, SZREG-1
 	andi	t1, t1, ~(SZREG-1)
 	/* dst is already aligned, skip */
-	beq	a0, t1, .Lskip_first_bytes
+	beq	a0, t1, .Lskip_align_dst
 1:
 	/* a5 - one byte for copying data */
 	fixup lb      a5, 0(a1), 10f
@@ -55,7 +55,7 @@ ENTRY(__asm_copy_from_user)
 	addi	a0, a0, 1	/* dst */
 	bltu	a0, t1, 1b	/* t1 - start of aligned dst */
 
-.Lskip_first_bytes:
+.Lskip_align_dst:
 	/*
 	 * Now dst is aligned.
 	 * Use shift-copy if src is misaligned.
@@ -72,10 +72,9 @@ ENTRY(__asm_copy_from_user)
 	 *
 	 * a0 - start of aligned dst
 	 * a1 - start of aligned src
-	 * a3 - a1 & mask:(SZREG-1)
 	 * t0 - end of aligned dst
 	 */
-	addi	t0, t0, -(8*SZREG-1) /* not to over run */
+	addi	t0, t0, -(8*SZREG) /* not to over run */
 2:
 	fixup REG_L   a4,        0(a1), 10f
 	fixup REG_L   a5,    SZREG(a1), 10f
@@ -97,7 +96,7 @@ ENTRY(__asm_copy_from_user)
 	addi	a1, a1, 8*SZREG
 	bltu	a0, t0, 2b
 
-	addi	t0, t0, 8*SZREG-1 /* revert to original value */
+	addi	t0, t0, 8*SZREG /* revert to original value */
 	j	.Lbyte_copy_tail
 
 .Lshift_copy:
@@ -107,7 +106,7 @@ ENTRY(__asm_copy_from_user)
 	 * For misaligned copy we still perform aligned word copy, but
 	 * we need to use the value fetched from the previous iteration and
 	 * do some shifts.
-	 * This is safe because reading less than a word size.
+	 * This is safe because reading is less than a word size.
 	 *
 	 * a0 - start of aligned dst
 	 * a1 - start of src
@@ -117,7 +116,7 @@ ENTRY(__asm_copy_from_user)
 	 */
 	/* calculating aligned word boundary for dst */
 	andi	t1, t0, ~(SZREG-1)
-	/* Converting unaligned src to aligned arc */
+	/* Converting unaligned src to aligned src */
 	andi	a1, a1, ~(SZREG-1)
 
 	/*
@@ -125,11 +124,11 @@ ENTRY(__asm_copy_from_user)
 	 * t3 - prev shift
 	 * t4 - current shift
 	 */
-	slli	t3, a3, LGREG
+	slli	t3, a3, 3 /* converting bytes in a3 to bits */
 	li	a5, SZREG*8
 	sub	t4, a5, t3
 
-	/* Load the first word to combine with seceond word */
+	/* Load the first word to combine with second word */
 	fixup REG_L   a5, 0(a1), 10f
 
 3:
@@ -161,7 +160,7 @@ ENTRY(__asm_copy_from_user)
 	 * a1 - start of remaining src
 	 * t0 - end of remaining dst
 	 */
-	bgeu	a0, t0, 5f
+	bgeu	a0, t0, .Lout_copy_user  /* check if end of copy */
 4:
 	fixup lb      a5, 0(a1), 10f
 	addi	a1, a1, 1	/* src */
@@ -169,7 +168,7 @@ ENTRY(__asm_copy_from_user)
 	addi	a0, a0, 1	/* dst */
 	bltu	a0, t0, 4b	/* t0 - end of dst */
 
-5:
+.Lout_copy_user:
 	/* Disable access to user memory */
 	csrc CSR_STATUS, t6
 	li	a0, 0