lib: sbi: Print scratch size and usage at boot time

The scratch space being a scarce resource so let us print it's
size and usage at boot time.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

include/sbi/sbi_scratch.h

@@ -175,6 +175,9 @@ unsigned long sbi_scratch_alloc_offset(unsigned long size);
 /** Free-up extra space in sbi_scratch */
 void sbi_scratch_free_offset(unsigned long offset);
 
+/** Amount (in bytes) of used space in in sbi_scratch */
+unsigned long sbi_scratch_used_space(void);
+
 /** Get pointer from offset in sbi_scratch */
 #define sbi_scratch_offset_ptr(scratch, offset)	(void *)((char *)(scratch) + (offset))
 

lib/sbi/sbi_init.c

@@ -128,6 +128,11 @@ static void sbi_boot_print_general(struct sbi_scratch *scratch)
 		   (u32)(sbi_heap_reserved_space() / 1024),
 		   (u32)(sbi_heap_used_space() / 1024),
 		   (u32)(sbi_heap_free_space() / 1024));
+	sbi_printf("Firmware Scratch Size     : "
+		   "%d B (total), %d B (used), %d B (free)\n",
+		   SBI_SCRATCH_SIZE,
+		   (u32)sbi_scratch_used_space(),
+		   (u32)(SBI_SCRATCH_SIZE - sbi_scratch_used_space()));
 
 	/* SBI details */
 	sbi_printf("Runtime SBI Version       : %d.%d\n",

lib/sbi/sbi_scratch.c

@@ -97,3 +97,14 @@ void sbi_scratch_free_offset(unsigned long offset)
 	 * brain-dead allocator.
 	 */
 }
+
+unsigned long sbi_scratch_used_space(void)
+{
+	unsigned long ret = 0;
+
+	spin_lock(&extra_lock);
+	ret = extra_offset;
+	spin_unlock(&extra_lock);
+
+	return ret;
+}