riscv: Call identify_cpu() earlier for CPU 0

It is advantageous to have knowledge of ISA features as early as
possible. For example, the presence of newer virtual memory extensions
may be useful to pmap_bootstrap().

To achieve this, split out the printf() parts of identify_cpu() into a
separate function, printcpuinfo(). This latter function will be called
later in boot after the console has been initialized.

Reviewed by:	markj
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D39810

sys/riscv/include/cpu.h

@@ -90,6 +90,7 @@ void	cpu_halt(void) __dead2;
 void	cpu_reset(void) __dead2;
 void	fork_trampoline(void);
 void	identify_cpu(void);
+void	printcpuinfo(void);
 
 static __inline uint64_t
 get_cyclecount(void)

sys/riscv/riscv/identcpu.c

@@ -365,6 +365,14 @@ identify_cpu_ids(struct cpu_desc *desc)
 
 void
 identify_cpu(void)
+{
+	struct cpu_desc *desc = &cpu_desc[PCPU_GET(cpuid)];
+
+	identify_cpu_ids(desc);
+}
+
+void
+printcpuinfo(void)
 {
 	struct cpu_desc *desc;
 	u_int cpu, hart;
@@ -373,8 +381,6 @@ identify_cpu(void)
 	hart = PCPU_GET(hart);
 	desc = &cpu_desc[cpu];
 
-	identify_cpu_ids(desc);
-
 	/* Print details for boot CPU or if we want verbose output */
 	if (cpu == 0 || bootverbose) {
 		/* Summary line. */

sys/riscv/riscv/machdep.c

@@ -128,7 +128,7 @@ cpu_startup(void *dummy)
 {
 
 	sbi_print_version();
-	identify_cpu();
+	printcpuinfo();
 
 	printf("real memory  = %ju (%ju MB)\n", ptoa((uintmax_t)realmem),
 	    ptoa((uintmax_t)realmem) / (1024 * 1024));
@@ -536,6 +536,11 @@ initriscv(struct riscv_bootparams *rvbp)
 	physmem_hardware_regions(mem_regions, mem_regions_sz);
 #endif
 
+	/*
+	 * Identify CPU/ISA features.
+	 */
+	identify_cpu();
+
 	/* Do basic tuning, hz etc */
 	init_param1();
 

sys/riscv/riscv/mp_machdep.c

@@ -255,6 +255,7 @@ init_secondary(uint64_t hart)
 	 * runtime chip identification.
 	 */
 	identify_cpu();
+	printcpuinfo();
 
 	/* Enable software interrupts */
 	riscv_unmask_ipi();