riscv: ax25: cache.c: Cleanups to L1/L2 cache function used in SPL

This patch refines L1 cache enable/disable and v5l2-cache enable
functions.

Signed-off-by: Yu Chien Peter Lin <peterlin@andestech.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
Reviewed-by: Rick Chen <rick@andestech.com>

arch/riscv/cpu/ax25/cache.c

@@ -1,57 +1,51 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * Copyright (C) 2017 Andes Technology Corporation
+ * Copyright (C) 2023 Andes Technology Corporation
  * Rick Chen, Andes Technology Corporation <rick@andestech.com>
  */
 
+#include <asm/csr.h>
+#include <asm/asm.h>
 #include <common.h>
+#include <cache.h>
 #include <cpu_func.h>
 #include <dm.h>
-#include <asm/cache.h>
 #include <dm/uclass-internal.h>
-#include <cache.h>
-#include <asm/csr.h>
-
-#ifdef CONFIG_RISCV_NDS_CACHE
-#if CONFIG_IS_ENABLED(RISCV_MMODE)
-/* mcctlcommand */
-#define CCTL_REG_MCCTLCOMMAND_NUM	0x7cc
-
-/* D-cache operation */
-#define CCTL_L1D_WBINVAL_ALL	6
-#endif
-#endif
+#include <asm/arch-andes/csr.h>
 
 #ifdef CONFIG_V5L2_CACHE
-static void _cache_enable(void)
+void enable_caches(void)
 {
-	struct udevice *dev = NULL;
-
-	uclass_find_first_device(UCLASS_CACHE, &dev);
-
-	if (dev)
-		cache_enable(dev);
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_get_device_by_driver(UCLASS_CACHE,
+					  DM_DRIVER_GET(v5l2_cache),
+					  &dev);
+	if (ret) {
+		log_debug("Cannot enable v5l2 cache\n");
+	} else {
+		ret = cache_enable(dev);
+		if (ret)
+			log_debug("v5l2 cache enable failed\n");
+	}
 }
 
-static void _cache_disable(void)
+static void cache_ops(int (*ops)(struct udevice *dev))
 {
 	struct udevice *dev = NULL;
 
 	uclass_find_first_device(UCLASS_CACHE, &dev);
 
 	if (dev)
-		cache_disable(dev);
+		ops(dev);
 }
 #endif
 
 void flush_dcache_all(void)
 {
-#if !CONFIG_IS_ENABLED(SYS_ICACHE_OFF)
-#ifdef CONFIG_RISCV_NDS_CACHE
 #if CONFIG_IS_ENABLED(RISCV_MMODE)
-	csr_write(CCTL_REG_MCCTLCOMMAND_NUM, CCTL_L1D_WBINVAL_ALL);
-#endif
-#endif
+	csr_write(CSR_MCCTLCOMMAND, CCTL_L1D_WBINVAL_ALL);
 #endif
 }
 
@@ -67,26 +61,70 @@ void invalidate_dcache_range(unsigned long start, unsigned long end)
 
 void icache_enable(void)
 {
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
+	asm volatile("csrsi %0, 0x1" :: "i"(CSR_MCACHE_CTL));
+#endif
 }
 
 void icache_disable(void)
 {
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
+	asm volatile("csrci %0, 0x1" :: "i"(CSR_MCACHE_CTL));
+#endif
 }
 
 void dcache_enable(void)
 {
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
+	asm volatile("csrsi %0, 0x2" :: "i"(CSR_MCACHE_CTL));
+#endif
+
+#ifdef CONFIG_V5L2_CACHE
+	cache_ops(cache_enable);
+#endif
 }
 
 void dcache_disable(void)
 {
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
+	asm volatile("csrci %0, 0x2" :: "i"(CSR_MCACHE_CTL));
+#endif
+
+#ifdef CONFIG_V5L2_CACHE
+	cache_ops(cache_disable);
+#endif
 }
 
 int icache_status(void)
 {
-	return 0;
+	int ret = 0;
+
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
+	asm volatile (
+		"csrr t1, %1\n\t"
+		"andi %0, t1, 0x01\n\t"
+		: "=r" (ret)
+		: "i"(CSR_MCACHE_CTL)
+		: "memory"
+	);
+#endif
+
+	return !!ret;
 }
 
 int dcache_status(void)
 {
-	return 0;
+	int ret = 0;
+
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
+	asm volatile (
+		"csrr t1, %1\n\t"
+		"andi %0, t1, 0x02\n\t"
+		: "=r" (ret)
+		: "i" (CSR_MCACHE_CTL)
+		: "memory"
+	);
+#endif
+
+	return !!ret;
 }