bch: Allow to build for the host

We will need the bch functions in the tool to generate the SPL images for
the Allwinner SoCs.

Do the needed adjustments so that we can use it on the host.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>

lib/bch.c

@@ -54,10 +54,27 @@
  * finite fields GF(2^q). In Rapport de recherche INRIA no 2829, 1996.
  */
 
+#ifndef USE_HOSTCC
 #include <common.h>
 #include <ubi_uboot.h>
 
 #include <linux/bitops.h>
+#else
+#include <errno.h>
+#include <endian.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#undef cpu_to_be32
+#define cpu_to_be32 htobe32
+#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
+#define kmalloc(size, flags)	malloc(size)
+#define kzalloc(size, flags)	calloc(1, size)
+#define kfree free
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+#endif
+
 #include <asm/byteorder.h>
 #include <linux/bch.h>
 
@@ -95,6 +112,37 @@ struct gf_poly_deg1 {
 	unsigned int   c[2];
 };
 
+#ifdef USE_HOSTCC
+static int fls(int x)
+{
+	int r = 32;
+
+	if (!x)
+		return 0;
+	if (!(x & 0xffff0000u)) {
+		x <<= 16;
+		r -= 16;
+	}
+	if (!(x & 0xff000000u)) {
+		x <<= 8;
+		r -= 8;
+	}
+	if (!(x & 0xf0000000u)) {
+		x <<= 4;
+		r -= 4;
+	}
+	if (!(x & 0xc0000000u)) {
+		x <<= 2;
+		r -= 2;
+	}
+	if (!(x & 0x80000000u)) {
+		x <<= 1;
+		r -= 1;
+	}
+	return r;
+}
+#endif
+
 /*
  * same as encode_bch(), but process input data one byte at a time
  */