Mitig: TMR more variables and some function calls

common/src/checksums.c

 #include <atmel_start.h>
 
+#include <COAST.h>
 #include "checksums.h"
 
-int sysv_checksum(uint8_t *start_addr, uint8_t *end_addr)
+int __xMR_FN_CALL sysv_checksum(uint8_t *start_addr, uint8_t *end_addr)
 {
         uint32_t result = 0;
         uint16_t result16 = 0;
@@ -13,7 +14,7 @@ int sysv_checksum(uint8_t *start_addr, uint8_t *end_addr)
         return (result16 & 0xffff) + (result16 >> 16);
 }
 
-uint8_t crc8_byte(uint8_t n)
+uint8_t __xMR_FN_CALL crc8_byte(uint8_t n)
 {
         uint8_t poly = 0x07; /* x^8 + x^2 + x + 1 */
         uint8_t crc = n;
@@ -25,11 +26,23 @@ uint8_t crc8_byte(uint8_t n)
         return crc;
 }
 
-uint8_t crc8_bytearray(uint8_t *na, uint8_t len)
+static uint8_t crc8_byte_notmr(uint8_t n)
+{
+        uint8_t poly = 0x07; /* x^8 + x^2 + x + 1 */
+        uint8_t crc = n;
+        for (uint8_t i = 0; i < 8; ++i)
+                if (crc & 0x80)
+                        crc = ((crc << 1) ^ poly);
+                else
+                        crc = (crc << 1);
+        return crc;
+}
+
+uint8_t __xMR_FN_CALL crc8_bytearray(uint8_t *na, uint8_t len)
 {
         uint8_t result = 0;
         for (uint8_t i = 0; i < len; ++i) {
-                result = crc8_byte(result ^ na[i]);
+                result = crc8_byte_notmr(result ^ na[i]);
         }
         return result;
 }

common/src/float_utils.c

 #include <atmel_start.h>
 #include <math.h>
+#include <COAST.h>
 
-uint16_t float_to_linear(float val)
+uint16_t __xMR_FN_CALL float_to_linear(float val)
 {
         // only works with positive numbers for now
         int32_t exp = ceilf(log2f(val) - log2f(1023));
@@ -20,7 +21,7 @@ uint16_t float_to_linear(float val)
 }
 
 
-float linear_to_float(uint16_t val)
+float __xMR_FN_CALL linear_to_float(uint16_t val)
 {
         int16_t exp = ((val & 0x8000)?0xffe0:0) | ((val >> 11) & 0x1f);
         int16_t man = ((val & 0x0400)?0xf800:0) | (val & 0x7ff);

common/src/i2c_slave.c

@@ -15,7 +15,7 @@
 #define send_nack(descr) hri_sercomi2cs_set_CTRLB_ACKACT_bit(descr->device.hw)
 #define set_cmd(descr, cmd) hri_sercomi2cs_write_CTRLB_CMD_bf(descr->device.hw, cmd);
 
-static struct io_descriptor *io;
+static struct io_descriptor *io __xMR;
 
 static uint16_t rx_state __xMR = CMD;
 static uint8_t std_cmd_addr;

main_fw/src/i2c_impl.c

 #include <atmel_start.h>
 #include <stdlib.h>
 
+#include <COAST.h>
 #include <i2c_slave.h>
 #include <flash_utils.h>
 #include <usb_debug.h>
@@ -13,7 +14,7 @@ const char MFR_DAT[] = "190801";
 const char MFR_SER[] = "123456789";
 
 void page_chk();
-uint8_t page;
+uint16_t page __xMR;
 
 void accvolt();
 void acccurr();
@@ -128,7 +129,7 @@ void boot_new_fw()
 }
 
 
-void page_chk()
+void __xMR page_chk()
 {
         if (page > 2)
                 page = 2;