soc/sdram: add L2_SIZE constant and avoid declaring an empty flush_l2_cache function when L2_SIZE is not defined

misoclib/soc/sdram.py

@@ -53,6 +53,8 @@ class SDRAMSoC(SoC):
         # XXX: Limit main_ram_size to 256MB, we should modify mem_map to allow larger memories.
         main_ram_size = min(main_ram_size, 256*1024*1024)
         l2_size = self.sdram_controller_settings.l2_size
+        if l2_size:
+            self.add_constant("L2_SIZE", l2_size)
 
         # add a Wishbone interface to the DRAM
         wb_sdram = wishbone.Interface()

software/bios/main.c

@@ -355,7 +355,10 @@ static void do_command(char *c)
 	else if(strcmp(token, "mw") == 0) mw(get_token(&c), get_token(&c), get_token(&c));
 	else if(strcmp(token, "mc") == 0) mc(get_token(&c), get_token(&c), get_token(&c));
 	else if(strcmp(token, "crc") == 0) crc(get_token(&c), get_token(&c));
+
+#ifdef L2_SIZE
 	else if(strcmp(token, "flushl2") == 0) flush_l2_cache();
+#endif
 
 #ifdef FLASH_BOOT_ADDRESS
 	else if(strcmp(token, "flashboot") == 0) flashboot();

software/libbase/system.c

@@ -67,16 +67,14 @@ void flush_cpu_dcache(void)
 #endif
 }
 
-#ifdef CSR_L2_CACHE_BASE
+#ifdef L2_SIZE
 void flush_l2_cache(void)
 {
-	unsigned int l2_nwords;
 	unsigned int i;
 	register unsigned int addr;
 	register unsigned int dummy;
 
-	l2_nwords = 1 << l2_cache_size_read();
-	for(i=0;i<2*l2_nwords;i++) {
+	for(i=0;i<2*L2_SIZE;i++) {
 		addr = MAIN_RAM_BASE + i*4;
 #if defined (__lm32__)
 		__asm__ volatile("lw %0, (%1+0)\n":"=r"(dummy):"r"(addr));
@@ -87,8 +85,4 @@ void flush_l2_cache(void)
 #endif
 	}
 }
-#else
-void flush_l2_cache(void)
-{
-}
 #endif