nios2: Add CDX support
Add support for the CDX Code Density Extensions present in
Nios II R2 . This introduces new 16bit instruction set to
improve code density while retaining support for the 32bit
Nios II R2 instructions.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <lftan@altera.com>
diff --git a/arch/nios2/Makefile b/arch/nios2/Makefile
index 74109c0..8673a79 100644
--- a/arch/nios2/Makefile
+++ b/arch/nios2/Makefile
@@ -30,6 +30,7 @@
KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_HW_MULX_SUPPORT),-mhw-mulx,-mno-hw-mulx)
KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_HW_DIV_SUPPORT),-mhw-div,-mno-hw-div)
KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_BMX_SUPPORT),-mbmx,-mno-bmx)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_CDX_SUPPORT),-mcdx,-mno-cdx)
KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_FPU_SUPPORT),-mcustom-fpu-cfg=60-1,)
KBUILD_CFLAGS += -fno-optimize-sibling-calls
diff --git a/arch/nios2/include/asm/cpuinfo.h b/arch/nios2/include/asm/cpuinfo.h
index 79d3764..dbdaf96 100644
--- a/arch/nios2/include/asm/cpuinfo.h
+++ b/arch/nios2/include/asm/cpuinfo.h
@@ -30,6 +30,7 @@ struct cpuinfo {
bool has_mul;
bool has_mulx;
bool has_bmx;
+ bool has_cdx;
/* CPU caches */
u32 icache_line_size;
diff --git a/arch/nios2/kernel/cpuinfo.c b/arch/nios2/kernel/cpuinfo.c
index 4c84fec..9320771 100644
--- a/arch/nios2/kernel/cpuinfo.c
+++ b/arch/nios2/kernel/cpuinfo.c
@@ -68,6 +68,7 @@ void __init setup_cpuinfo(void)
cpuinfo.has_mul = of_property_read_bool(cpu, "altr,has-mul");
cpuinfo.has_mulx = of_property_read_bool(cpu, "altr,has-mulx");
cpuinfo.has_bmx = of_property_read_bool(cpu, "altr,has-bmx");
+ cpuinfo.has_cdx = of_property_read_bool(cpu, "altr,has-cdx");
cpuinfo.mmu = of_property_read_bool(cpu, "altr,has-mmu");
if (IS_ENABLED(CONFIG_NIOS2_HW_DIV_SUPPORT) && !cpuinfo.has_div)
@@ -82,6 +83,9 @@ void __init setup_cpuinfo(void)
if (IS_ENABLED(CONFIG_NIOS2_BMX_SUPPORT) && !cpuinfo.has_bmx)
err_cpu("BMX");
+ if (IS_ENABLED(CONFIG_NIOS2_CDX_SUPPORT) && !cpuinfo.has_cdx)
+ err_cpu("CDX");
+
cpuinfo.tlb_num_ways = fcpu(cpu, "altr,tlb-num-ways");
if (!cpuinfo.tlb_num_ways)
panic("altr,tlb-num-ways can't be 0. Please check your hardware "
@@ -148,11 +152,13 @@ static int show_cpuinfo(struct seq_file *m, void *v)
" MUL:\t\t%s\n"
" MULX:\t\t%s\n"
" DIV:\t\t%s\n"
- " BMX:\t\t%s\n",
+ " BMX:\t\t%s\n"
+ " CDX:\t\t%s\n",
cpuinfo.has_mul ? "yes" : "no",
cpuinfo.has_mulx ? "yes" : "no",
cpuinfo.has_div ? "yes" : "no",
- cpuinfo.has_bmx ? "yes" : "no");
+ cpuinfo.has_bmx ? "yes" : "no",
+ cpuinfo.has_cdx ? "yes" : "no");
seq_printf(m,
"Icache:\t\t%ukB, line length: %u\n",
diff --git a/arch/nios2/platform/Kconfig.platform b/arch/nios2/platform/Kconfig.platform
index b6a8bfd..74c1aaf 100644
--- a/arch/nios2/platform/Kconfig.platform
+++ b/arch/nios2/platform/Kconfig.platform
@@ -90,6 +90,15 @@
the BMX Bit Manipulation Extension instructions. Enables
the -mbmx compiler flag.
+config NIOS2_CDX_SUPPORT
+ bool "Enable CDX instructions"
+ depends on NIOS2_ARCH_REVISION = 2
+ default n
+ help
+ Set to true if you configured the Nios II R2 to include
+ the CDX Bit Manipulation Extension instructions. Enables
+ the -mcdx compiler flag.
+
config NIOS2_FPU_SUPPORT
bool "Custom floating point instr support"
default n
