[PATCH] riscv: Skip riscv_cpu_setup() when CPU driver is disabled

[Michal Simek]

Building on commit c64fc632a86a ("riscv: cpu: Use CONFIG_IS_ENABLED(CPU)
instead of plain ifdef"), add an early return in riscv_cpu_setup() when
CONFIG_CPU is not enabled. This allows platforms to save code space in
SPL by disabling CONFIG_SPL_CPU.

The compiler's dead-code elimination combined with --gc-sections
removes the unreachable code and all associated static data,
achieving significant size reduction without preprocessor guards:

  spl/u-boot-spl:all -4332 spl/u-boot-spl:rodata -2872
  spl/u-boot-spl:text -1460

Signed-off-by: Michal Simek <michal.simek at amd.com>
---

 arch/riscv/cpu/cpu.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
index bbadd0c9a469..3bec7c7cb6d0 100644
--- a/arch/riscv/cpu/cpu.c
+++ b/arch/riscv/cpu/cpu.c
@@ -638,6 +638,9 @@ int riscv_cpu_setup(void)
 	const char *isa, **exts;
 	struct udevice *dev;
 
+	if (!CONFIG_IS_ENABLED(CPU))
+		return 0;
+
 	uclass_find_first_device(UCLASS_CPU, &dev);
 	if (!dev) {
 		debug("unable to find the RISC-V cpu device\n");
-- 
2.43.0

base-commit: ab9f3cb4de54c65bde394e31469c75ec89b18d5b