[U-Boot] [PATCH 12/19] riscv: Do some basic architecture level cpu initialization

[Bin Meng]

Implement arch_cpu_init() to do some basic architecture level cpu
initialization, like FPU enable, etc.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
---

 arch/riscv/cpu/cpu.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
index d9f820c..4e508cf 100644
--- a/arch/riscv/cpu/cpu.c
+++ b/arch/riscv/cpu/cpu.c
@@ -5,6 +5,7 @@
 
 #include <common.h>
 #include <asm/csr.h>
+#include <asm/encoding.h>
 
 /*
  * prior_stage_fdt_address must be stored in the data section since it is used
@@ -53,3 +54,23 @@ int print_cpuinfo(void)
 
 	return 0;
 }
+
+int arch_cpu_init(void)
+{
+	/* Enable FPU */
+	if (supports_extension('d') || supports_extension('f')) {
+		csr_write(mstatus, MSTATUS_FS);
+		csr_write(fcsr, 0);
+	}
+
+	/* Enable user/supervisor use of perf counters */
+	if (supports_extension('s'))
+		csr_write(scounteren, -1);
+	csr_write(mcounteren, -1);
+
+	/* Disable paging */
+	if (supports_extension('s'))
+		csr_write(sptbr, 0);
+
+	return 0;
+}
-- 
2.7.4