ARCv2: boot log: updates for HS48: dual-issue, ECC, Loop Buffer

Print the hardware support for ECC, Loop Buffer as well as the runtime
enabled status

Note that unlike the existing boot printing, this one is not read from
pre-decoded hardware capabilty info cached in cpuinfo[] struct.
Instead we read the AUX regs on the spot and print it, without botherign
to save anywhere.

There is no point in saving static hardware capabilites in memory when
its use is very sporadic and non-performance critical, mainly for
/proc/cpuinfo. This gets worse in SMP, given it is per-cpu, and pretty
much exactly same across all cpus. So only info needed at runtime
(e.g. TLB geometry) needs to be cached in cpuinfo[]. So going fwd
we will start converting code to this paradigm.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/include/asm/arcregs.h

@@ -11,12 +11,14 @@
 
 /* Build Configuration Registers */
 #define ARC_REG_AUX_DCCM	0x18	/* DCCM Base Addr ARCv2 */
+#define ARC_REG_ERP_CTRL	0x3F	/* ARCv2 Error protection control */
 #define ARC_REG_DCCM_BASE_BUILD	0x61	/* DCCM Base Addr ARCompact */
 #define ARC_REG_CRC_BCR		0x62
 #define ARC_REG_VECBASE_BCR	0x68
 #define ARC_REG_PERIBASE_BCR	0x69
 #define ARC_REG_FP_BCR		0x6B	/* ARCompact: Single-Precision FPU */
 #define ARC_REG_DPFP_BCR	0x6C	/* ARCompact: Dbl Precision FPU */
+#define ARC_REG_ERP_BUILD	0xc7	/* ARCv2 Error protection Build: ECC/Parity */
 #define ARC_REG_FP_V2_BCR	0xc8	/* ARCv2 FPU */
 #define ARC_REG_SLC_BCR		0xce
 #define ARC_REG_DCCM_BUILD	0x74	/* DCCM size (common) */
@@ -32,11 +34,14 @@
 #define ARC_REG_D_UNCACH_BCR	0x6A
 #define ARC_REG_BPU_BCR		0xc0
 #define ARC_REG_ISA_CFG_BCR	0xc1
+#define ARC_REG_LPB_BUILD	0xE9	/* ARCv2 Loop Buffer Build */
 #define ARC_REG_RTT_BCR		0xF2
 #define ARC_REG_IRQ_BCR		0xF3
+#define ARC_REG_MICRO_ARCH_BCR	0xF9	/* ARCv2 Product revision */
 #define ARC_REG_SMART_BCR	0xFF
 #define ARC_REG_CLUSTER_BCR	0xcf
 #define ARC_REG_AUX_ICCM	0x208	/* ICCM Base Addr (ARCv2) */
+#define ARC_REG_LPB_CTRL	0x488	/* ARCv2 Loop Buffer control */
 
 /* Common for ARCompact and ARCv2 status register */
 #define ARC_REG_STATUS32	0x0A
@@ -229,6 +234,32 @@ struct bcr_bpu_arcv2 {
 #endif
 };
 
+/* Error Protection Build: ECC/Parity */
+struct bcr_erp {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	unsigned int pad3:5, mmu:3, pad2:4, ic:3, dc:3, pad1:6, ver:8;
+#else
+	unsigned int ver:8, pad1:6, dc:3, ic:3, pad2:4, mmu:3, pad3:5;
+#endif
+};
+
+/* Error Protection Control */
+struct ctl_erp {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	unsigned int pad2:27, mpd:1, pad1:2, dpd:1, dpi:1;
+#else
+	unsigned int dpi:1, dpd:1, pad1:2, mpd:1, pad2:27;
+#endif
+};
+
+struct bcr_lpb {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	unsigned int pad:16, entries:8, ver:8;
+#else
+	unsigned int ver:8, entries:8, pad:16;
+#endif
+};
+
 struct bcr_generic {
 #ifdef CONFIG_CPU_BIG_ENDIAN
 	unsigned int info:24, ver:8;
@@ -270,7 +301,7 @@ struct cpuinfo_arc {
 	struct cpuinfo_arc_ccm iccm, dccm;
 	struct {
 		unsigned int swap:1, norm:1, minmax:1, barrel:1, crc:1, swape:1, pad1:2,
-			     fpu_sp:1, fpu_dp:1, dual_iss_enb:1, dual_iss_exist:1, pad2:4,
+			     fpu_sp:1, fpu_dp:1, dual:1, dual_enb:1, pad2:4,
 			     debug:1, ap:1, smart:1, rtt:1, pad3:4,
 			     timer0:1, timer1:1, rtc:1, gfrc:1, pad4:4;
 	} extn;

arch/arc/kernel/setup.c

@@ -199,8 +199,10 @@ static void read_arc_build_cfg_regs(void)
 			unsigned int exec_ctrl;
 
 			READ_BCR(AUX_EXEC_CTRL, exec_ctrl);
-			cpu->extn.dual_iss_exist = 1;
-			cpu->extn.dual_iss_enb = exec_ctrl & 1;
+			cpu->extn.dual_enb = exec_ctrl & 1;
+
+			/* dual issue always present for this core */
+			cpu->extn.dual = 1;
 		}
 	}
 
@@ -253,7 +255,7 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 		       cpu_id, cpu->name, cpu->details,
 		       is_isa_arcompact() ? "ARCompact" : "ARCv2",
 		       IS_AVAIL1(cpu->isa.be, "[Big-Endian]"),
-		       IS_AVAIL3(cpu->extn.dual_iss_exist, cpu->extn.dual_iss_enb, " Dual-Issue"));
+		       IS_AVAIL3(cpu->extn.dual, cpu->extn.dual_enb, " Dual-Issue "));
 
 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s%s%s\nISA Extn\t: ",
 		       IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
@@ -293,11 +295,26 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 
 	if (cpu->bpu.ver)
 		n += scnprintf(buf + n, len - n,
-			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
+			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d",
 			      IS_AVAIL1(cpu->bpu.full, "full"),
 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
 
+	if (is_isa_arcv2()) {
+		struct bcr_lpb lpb;
+
+		READ_BCR(ARC_REG_LPB_BUILD, lpb);
+		if (lpb.ver) {
+			unsigned int ctl;
+			ctl = read_aux_reg(ARC_REG_LPB_CTRL);
+
+			n += scnprintf(buf + n, len - n, " Loop Buffer:%d %s",
+				lpb.entries,
+				IS_DISABLED_RUN(!ctl));
+		}
+	}
+
+	n += scnprintf(buf + n, len - n, "\n");
 	return buf;
 }
 
@@ -326,6 +343,24 @@ static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
 
+	if (is_isa_arcv2()) {
+
+		/* Error Protection: ECC/Parity */
+		struct bcr_erp erp;
+		READ_BCR(ARC_REG_ERP_BUILD, erp);
+
+		if (erp.ver) {
+			struct  ctl_erp ctl;
+			READ_BCR(ARC_REG_ERP_CTRL, ctl);
+
+			/* inverted bits: 0 means enabled */
+			n += scnprintf(buf + n, len - n, "Extn [ECC]\t: %s%s%s%s%s%s\n",
+				IS_AVAIL3(erp.ic,  !ctl.dpi, "IC "),
+				IS_AVAIL3(erp.dc,  !ctl.dpd, "DC "),
+				IS_AVAIL3(erp.mmu, !ctl.mpd, "MMU "));
+		}
+	}
+
 	n += scnprintf(buf + n, len - n, "OS ABI [v%d]\t: %s\n",
 			EF_ARC_OSABI_CURRENT >> 8,
 			EF_ARC_OSABI_CURRENT == EF_ARC_OSABI_V3 ?