MIPS: BMIPS: fix slave CPU booting when physical CPU is not 0

The current BMIPS SMP code assumes that the slave CPU is physical and
logical CPU 1, but on some systems such as BCM3368, the slave CPU is
physical CPU0. Fix the code to read the physical CPU (thread ID) we are
running this code on, and adjust the relocation vector address based on
it. This allows bringing up the second CPU on BCM3368 for instance.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: cernekee@gmail.com
Cc: jogo@openwrt.org
Cc: blogic@openwrt.org
Patchwork: https://patchwork.linux-mips.org/patch/5621/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 13 insertions, 3 deletions

diff --git a/arch/mips/kernel/bmips_vec.S b/arch/mips/kernel/bmips_vec.S
index f739aedcb509..bd79c4f9bff4 100644
--- a/arch/mips/kernel/bmips_vec.S
+++ b/arch/mips/kernel/bmips_vec.S
@@ -54,7 +54,11 @@ LEAF(bmips_smp_movevec)
         /* set up CPU1 CBR; move BASE to 0xa000_0000 */
         li      k0, 0xff400000
         mtc0    k0, $22, 6
-        li      k1, CKSEG1 | BMIPS_RELO_VECTOR_CONTROL_1
+        /* set up relocation vector address based on thread ID */
+        mfc0    k1, $22, 3
+        srl     k1, 16
+        andi    k1, 0x8000
+        or      k1, CKSEG1 | BMIPS_RELO_VECTOR_CONTROL_0
         or      k0, k1
         li      k1, 0xa0080000
         sw      k1, 0(k0)
diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
index 89417c9c6aca..159abc8842d2 100644
--- a/arch/mips/kernel/smp-bmips.c
+++ b/arch/mips/kernel/smp-bmips.c
@@ -196,9 +196,15 @@ static void bmips_init_secondary(void)
 #if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
         void __iomem *cbr = BMIPS_GET_CBR();
         unsigned long old_vec;
+        unsigned long relo_vector;
+        int boot_cpu;
 
-        old_vec = __raw_readl(cbr + BMIPS_RELO_VECTOR_CONTROL_1);
-        __raw_writel(old_vec & ~0x20000000, cbr + BMIPS_RELO_VECTOR_CONTROL_1);
+        boot_cpu = !!(read_c0_brcm_cmt_local() & (1 << 31));
+        relo_vector = boot_cpu ? BMIPS_RELO_VECTOR_CONTROL_0 :
+                          BMIPS_RELO_VECTOR_CONTROL_1;
+
+        old_vec = __raw_readl(cbr + relo_vector);
+        __raw_writel(old_vec & ~0x20000000, cbr + relo_vector);
 
         clear_c0_cause(smp_processor_id() ? C_SW1 : C_SW0);
 #elif defined(CONFIG_CPU_BMIPS5000)