MIPS: Netlogic: Add support for XLP2XX

XLP2XX is first in the series of 28nm XLPII processors.

The changes are to:
* Add processor ID for XLP2XX to asm/cpu.h and kernel/cpu-probe.c.
* Add a cpu_is_xlpii() function to check for XLPII processors.
* Update xlp_mmu_init() to use config4 to enable extended TLB.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5698/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/cpu.h

@@ -179,6 +179,7 @@
 
 #define PRID_IMP_NETLOGIC_XLP8XX	0x1000
 #define PRID_IMP_NETLOGIC_XLP3XX	0x1100
+#define PRID_IMP_NETLOGIC_XLP2XX	0x1200
 
 /*
  * Definitions for 7:0 on legacy processors

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

@@ -64,5 +64,12 @@ int xlp_get_dram_map(int n, uint64_t *dram_map);
 /* Device tree related */
 void *xlp_dt_init(void *fdtp);
 
+static inline int cpu_is_xlpii(void)
+{
+	int chip = read_c0_prid() & 0xff00;
+
+	return chip == PRID_IMP_NETLOGIC_XLP2XX;
+}
+
 #endif /* !__ASSEMBLY__ */
 #endif /* _ASM_NLM_XLP_H */

arch/mips/kernel/cpu-probe.c

@@ -906,6 +906,11 @@ static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
 			MIPS_CPU_LLSC);
 
 	switch (c->processor_id & 0xff00) {
+	case PRID_IMP_NETLOGIC_XLP2XX:
+		c->cputype = CPU_XLP;
+		__cpu_name[cpu] = "Broadcom XLPII";
+		break;
+
 	case PRID_IMP_NETLOGIC_XLP8XX:
 	case PRID_IMP_NETLOGIC_XLP3XX:
 		c->cputype = CPU_XLP;

arch/mips/netlogic/xlp/setup.c

@@ -110,7 +110,12 @@ void __init plat_mem_setup(void)
 
 const char *get_system_type(void)
 {
+	switch (read_c0_prid() & 0xff00) {
+	case PRID_IMP_NETLOGIC_XLP2XX:
+		return "Broadcom XLPII Series";
+	default:
 		return "Netlogic XLP Series";
+	}
 }
 
 void __init prom_free_prom_memory(void)
@@ -120,12 +125,20 @@ void __init prom_free_prom_memory(void)
 
 void xlp_mmu_init(void)
 {
+	u32 conf4;
+
+	if (cpu_is_xlpii()) {
+		/* XLPII series has extended pagesize in config 4 */
+		conf4 = read_c0_config4() & ~0x1f00u;
+		write_c0_config4(conf4 | ((PAGE_SHIFT - 10) / 2 << 8));
+	} else {
 		/* enable extended TLB and Large Fixed TLB */
 		write_c0_config6(read_c0_config6() | 0x24);
 
-	/* set page mask of Fixed TLB in config7 */
+		/* set page mask of extended Fixed TLB in config7 */
 		write_c0_config7(PM_DEFAULT_MASK >>
 			(13 + (ffz(PM_DEFAULT_MASK >> 13) / 2)));
+	}
 }
 
 void nlm_percpu_init(int hwcpuid)