MIPS: Netlogic: SMP wakeup code update

Update for core intialization code.  Initialize status register
after receiving NMI for CPU wakeup. Add the low level L1D flush
code before enabling threads in core.

Also convert the ehb to _ehb so that it works under more GCC
versions.
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3755/
Patchwork: https://patchwork.linux-mips.org/patch/4095/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/netlogic/xlp-hal/cpucontrol.h

@@ -47,7 +47,9 @@
 #define CPU_BLOCKID_MAP		10
 
 #define LSU_DEFEATURE		0x304
-#define LSU_CERRLOG_REGID	0x09
+#define LSU_DEBUG_ADDR		0x305
+#define LSU_DEBUG_DATA0		0x306
+#define LSU_CERRLOG_REGID	0x309
 #define SCHED_DEFEATURE		0x700
 
 /* Offsets of interest from the 'MAP' Block */

arch/mips/netlogic/common/smpboot.S

@@ -80,6 +80,38 @@
  * This is the code that will be copied to the reset entry point for
  * XLR and XLP. The XLP cores start here when they are woken up. This
  * is also the NMI entry point.
+ */
+.macro	xlp_flush_l1_dcache
+	li	t0, LSU_DEBUG_DATA0
+	li	t1, LSU_DEBUG_ADDR
+	li	t2, 0		/* index */
+	li 	t3, 0x1000	/* loop count */
+1:
+	sll	v0, t2, 5
+	mtcr	zero, t0
+	ori	v1, v0, 0x3	/* way0 | write_enable | write_active */
+	mtcr	v1, t1
+2:
+	mfcr	v1, t1
+	andi	v1, 0x1		/* wait for write_active == 0 */
+	bnez	v1, 2b
+	nop
+	mtcr	zero, t0
+	ori	v1, v0, 0x7	/* way1 | write_enable | write_active */
+	mtcr	v1, t1
+3:
+	mfcr	v1, t1
+	andi	v1, 0x1		/* wait for write_active == 0 */
+	bnez	v1, 3b
+	nop
+	addi	t2, 1
+	bne	t3, t2, 1b
+	nop
+.endm
+
+/*
+ * The cores can come start when they are woken up. This is also the NMI
+ * entry, so check that first.
  *
  * The data corresponding to reset/NMI is stored at RESET_DATA_PHYS
  * location, this will have the thread mask (used when core is woken up)
@@ -138,6 +170,8 @@ FEXPORT(nlm_reset_entry)
  * a core.
  */
 EXPORT(nlm_boot_siblings)
+	/* core L1D flush before enable threads */
+	xlp_flush_l1_dcache
 	/* Enable hw threads by writing to MAP_THREADMODE of the core */
 	li	t0, CKSEG1ADDR(RESET_DATA_PHYS)
 	lw	t1, BOOT_THREAD_MODE(t0)	/* t1 <- thread mode */
@@ -164,16 +198,13 @@ EXPORT(nlm_boot_siblings)
         li	t0, MMU_SETUP
         li	t1, 0
         mtcr	t1, t0
-	ehb
+	_ehb
 
 2:	beqz	v0, 4f		/* boot cpu (cpuid == 0)? */
 	nop
 
 	/* setup status reg */
-	mfc0	t1, CP0_STATUS
-	li	t0, ST0_BEV
-	or	t1, t0
-	xor	t1, t0
+	move	t1, zero
 #ifdef CONFIG_64BIT
 	ori	t1, ST0_KX
 #endif
@@ -220,6 +251,12 @@ FEXPORT(xlp_boot_core0_siblings)	/* "Master" cpu starts from here */
 
 	__CPUINIT
 NESTED(nlm_boot_secondary_cpus, 16, sp)
+	/* Initialize CP0 Status */
+	move	t1, zero
+#ifdef CONFIG_64BIT
+	ori	t1, ST0_KX
+#endif
+	mtc0	t1, CP0_STATUS
 	PTR_LA	t1, nlm_next_sp
 	PTR_L	sp, 0(t1)
 	PTR_LA	t1, nlm_next_gp