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ARM: PJ4: don't use PJ4B code on PJ4

RFC New Arnd Bergmann 1 participant 1 message Dec 11, 2015 Arm (32-bit)

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RFC 1/1 ARM: PJ4: don't use PJ4B code on PJ4

We can have multiplatform kernels with PJ4 (Dove, MMP2) in combination with PJ4B (Armada 370) or PJ4B-MP (Berlin, Armada XP), and the processor functions that are defined for PJ4B use a mask that covers all three core types, rather than using the default ARMv7 type for the original PJ4.

This adds a second entry for PJ4B-MP, so we at least get a consistent behavior between single-machine kernels and combined ones.

I suspect however that we actually want different contents for each of the three cores, as PJ4B and PJ4B-MP appear to be at least as different as PJ4 is from PJ4B, in particular the support for the standard architecture extensions like IDIV and LPAE, and the PJ4B_ERRATA_4742 workaround apparently does not apply to PJ4B-MP but might apply to PJ4.

Fixes 049be07053eb ("ARM: 7754/1: Fix the CPU ID and the mask associated to the PJ4B")

---
I haven't even build tested this one, for now, let's use this to start the discussion about whether the bug is real and what the actual functions should be for each of the three cores.

arch/arm/mm/proc-v7.S +9 -2
index 8e1ea433c3f1..d7b61aa9cda9 100644
@@ -567,10 +567,17 @@ __v7_ca8_proc_info:
 #ifdef CONFIG_CPU_PJ4B
 	.type   __v7_pj4b_proc_info, #object
 __v7_pj4b_proc_info:
-	.long	0x560f5800
-	.long	0xff0fff00
+	.long	0x562f5840
+	.long	0xfffffff0
 	__v7_proc __v7_pj4b_proc_info, __v7_pj4b_setup, proc_fns = pj4b_processor_functions
 	.size	__v7_pj4b_proc_info, . - __v7_pj4b_proc_info
+
+	.type   __v7_pj4bmp_proc_info, #object
+__v7_pj4bmp_proc_info:
+	.long	0x561f5810
+	.long	0xfffffff0
+	__v7_proc __v7_pj4bmp_proc_info, __v7_pj4b_setup, proc_fns = pj4b_processor_functions
+	.size	__v7_pj4bmp_proc_info, . - __v7_pj4bmp_proc_info
 #endif
 
 	/*