From: Paul Burton <paul.burton@imgtec.com>
Date: Wed, 16 Apr 2014 10:10:57 +0000 (+0100)
Subject: MIPS: smp-cps: duplicate core0 CCA on secondary cores
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=0155a06529d4c8425573596720829b6c578c05f2;p=openwrt%2Fstaging%2Fblogic.git

MIPS: smp-cps: duplicate core0 CCA on secondary cores

Rather than hardcoding CCA=0x5 for secondary cores, re-use the CCA from
the boot CPU. This allows overrides of the CCA using the cca= kernel
parameter to take effect on all CPUs for consistency.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
---

diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S
index 1c865ae922a5..6f4f739dad96 100644
--- a/arch/mips/kernel/cps-vec.S
+++ b/arch/mips/kernel/cps-vec.S
@@ -45,10 +45,12 @@
 
 LEAF(mips_cps_core_entry)
 	/*
-	 * These first 8 bytes will be patched by cps_smp_setup to load the
-	 * base address of the CM GCRs into register v1.
+	 * These first 12 bytes will be patched by cps_smp_setup to load the
+	 * base address of the CM GCRs into register v1 and the CCA to use into
+	 * register s0.
 	 */
 	.quad	0
+	.word	0
 
 	/* Check whether we're here due to an NMI */
 	mfc0	k0, CP0_STATUS
@@ -139,10 +141,11 @@ icache_done:
 	 add	a0, a0, t0
 dcache_done:
 
-	/* Set Kseg0 cacheable, coherent, write-back, write-allocate */
+	/* Set Kseg0 CCA to that in s0 */
 	mfc0	t0, CP0_CONFIG
 	ori	t0, 0x7
-	xori	t0, 0x2
+	xori	t0, 0x7
+	or	t0, t0, s0
 	mtc0	t0, CP0_CONFIG
 	ehb
 
diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
index 6b96fedf0407..9e21bdd47043 100644
--- a/arch/mips/kernel/smp-cps.c
+++ b/arch/mips/kernel/smp-cps.c
@@ -123,9 +123,15 @@ static void __init cps_prepare_cpus(unsigned int max_cpus)
 		}
 	}
 
-	/* Patch the start of mips_cps_core_entry to provide the CM base */
+	/*
+	 * Patch the start of mips_cps_core_entry to provide:
+	 *
+	 * v0 = CM base address
+	 * s0 = kseg0 CCA
+	 */
 	entry_code = (u32 *)&mips_cps_core_entry;
 	UASM_i_LA(&entry_code, 3, (long)mips_cm_base);
+	uasm_i_addiu(&entry_code, 16, 0, cca);
 	dma_cache_wback_inv((unsigned long)&mips_cps_core_entry,
 			    (void *)entry_code - (void *)&mips_cps_core_entry);