MIPS: Detect DSP v3 support

DSPv3 is supported on all MIPSr6 systems which indicate support for DSPv2.

This doesn't require any changes to the kernel's handling of DSP
resources. The patch is to detect support and indicate it in /proc/cpuinfo

DSP v3 introduces a new instruction BPOSGE32C

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12918/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/cpu-features.h

@@ -307,6 +307,10 @@
 #define cpu_has_dsp2		(cpu_data[0].ases & MIPS_ASE_DSP2P)
 #endif
 
+#ifndef cpu_has_dsp3
+#define cpu_has_dsp3		(cpu_data[0].ases & MIPS_ASE_DSP3)
+#endif
+
 #ifndef cpu_has_mipsmt
 #define cpu_has_mipsmt		(cpu_data[0].ases & MIPS_ASE_MIPSMT)
 #endif

arch/mips/include/asm/cpu.h

@@ -413,5 +413,6 @@ enum cpu_type_enum {
 #define MIPS_ASE_DSP2P		0x00000040 /* Signal Processing ASE Rev 2 */
 #define MIPS_ASE_VZ		0x00000080 /* Virtualization ASE */
 #define MIPS_ASE_MSA		0x00000100 /* MIPS SIMD Architecture */
+#define MIPS_ASE_DSP3		0x00000200 /* Signal Processing ASE Rev 3*/
 
 #endif /* _ASM_CPU_H */

arch/mips/kernel/cpu-probe.c

@@ -680,8 +680,11 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c)
 		c->options |= MIPS_CPU_RIXI;
 	if (config3 & MIPS_CONF3_DSP)
 		c->ases |= MIPS_ASE_DSP;
-	if (config3 & MIPS_CONF3_DSP2P)
+	if (config3 & MIPS_CONF3_DSP2P) {
 		c->ases |= MIPS_ASE_DSP2P;
+		if (cpu_has_mips_r6)
+			c->ases |= MIPS_ASE_DSP3;
+	}
 	if (config3 & MIPS_CONF3_VINT)
 		c->options |= MIPS_CPU_VINT;
 	if (config3 & MIPS_CONF3_VEIC)

arch/mips/kernel/proc.c

@@ -114,6 +114,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 	if (cpu_has_smartmips)	seq_printf(m, "%s", " smartmips");
 	if (cpu_has_dsp)	seq_printf(m, "%s", " dsp");
 	if (cpu_has_dsp2)	seq_printf(m, "%s", " dsp2");
+	if (cpu_has_dsp3)	seq_printf(m, "%s", " dsp3");
 	if (cpu_has_mipsmt)	seq_printf(m, "%s", " mt");
 	if (cpu_has_mmips)	seq_printf(m, "%s", " micromips");
 	if (cpu_has_vz)		seq_printf(m, "%s", " vz");