armv8/fsl-lsch3: Convert flushing L3 to assembly to avoid using stack
Flushing L3 cache in CCN-504 requries d-cache to be disabled. Using
assembly function to guarantee stack is not used before flushing is
completed. Timeout is needed for simualtor on which CCN-504 is not
implemented. Return value can be checked for timeout situation.
Change bootm.c to disable dcache instead of simply flushing, required
by flushing L3.
Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S b/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S
index c283787..886576e 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S
+++ b/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S
@@ -100,6 +100,84 @@
ret
ENDPROC(lowlevel_init)
+hnf_pstate_poll:
+ /* x0 has the desired status, return 0 for success, 1 for timeout
+ * clobber x1, x2, x3, x4, x6, x7
+ */
+ mov x1, x0
+ mov x7, #0 /* flag for timeout */
+ mrs x3, cntpct_el0 /* read timer */
+ add x3, x3, #1200 /* timeout after 100 microseconds */
+ mov x0, #0x18
+ movk x0, #0x420, lsl #16 /* HNF0_PSTATE_STATUS */
+ mov w6, #8 /* HN-F node count */
+1:
+ ldr x2, [x0]
+ cmp x2, x1 /* check status */
+ b.eq 2f
+ mrs x4, cntpct_el0
+ cmp x4, x3
+ b.ls 1b
+ mov x7, #1 /* timeout */
+ b 3f
+2:
+ add x0, x0, #0x10000 /* move to next node */
+ subs w6, w6, #1
+ cbnz w6, 1b
+3:
+ mov x0, x7
+ ret
+
+hnf_set_pstate:
+ /* x0 has the desired state, clobber x1, x2, x6 */
+ mov x1, x0
+ /* power state to SFONLY */
+ mov w6, #8 /* HN-F node count */
+ mov x0, #0x10
+ movk x0, #0x420, lsl #16 /* HNF0_PSTATE_REQ */
+1: /* set pstate to sfonly */
+ ldr x2, [x0]
+ and x2, x2, #0xfffffffffffffffc /* & HNFPSTAT_MASK */
+ orr x2, x2, x1
+ str x2, [x0]
+ add x0, x0, #0x10000 /* move to next node */
+ subs w6, w6, #1
+ cbnz w6, 1b
+
+ ret
+
+ENTRY(__asm_flush_l3_cache)
+ /*
+ * Return status in x0
+ * success 0
+ * tmeout 1 for setting SFONLY, 2 for FAM, 3 for both
+ */
+ mov x29, lr
+ mov x8, #0
+
+ dsb sy
+ mov x0, #0x1 /* HNFPSTAT_SFONLY */
+ bl hnf_set_pstate
+
+ mov x0, #0x4 /* SFONLY status */
+ bl hnf_pstate_poll
+ cbz x0, 1f
+ mov x8, #1 /* timeout */
+1:
+ dsb sy
+ mov x0, #0x3 /* HNFPSTAT_FAM */
+ bl hnf_set_pstate
+
+ mov x0, #0xc /* FAM status */
+ bl hnf_pstate_poll
+ cbz x0, 1f
+ add x8, x8, #0x2
+1:
+ mov x0, x8
+ mov lr, x29
+ ret
+ENDPROC(__asm_flush_l3_cache)
+
/* Keep literals not used by the secondary boot code outside it */
.ltorg