cc2530: Added a method to maximise stack depth

This was oringinally contributed/reported/discussed/patched by
Philippe Retornaz (EPFL) but it's implemented
in a more configurable fashion here.

cpu/cc253x/8051def.h

@@ -56,6 +56,26 @@
 #define CC_NON_BANKED
 #endif
 
+/*
+ * Max Stack Depth manipulation. It is possible to get up to 247 bytes
+ * allocated for the stack if:
+ * - You set this to 1 and
+ * - You have a patched toolchain and
+ * - You don't use __bit variables
+ * - You do not link libraries using BIT registers (e.g. printf_large)
+ * Enabling this will mean ISRs will NOT push bits (#pragma exclude bits) so
+ * make sure you know what you're doing
+ *
+ * More information on the wiki
+ */
+#define CC_CONF_OPTIMIZE_STACK_SIZE 0
+
+#if CC_CONF_OPTIMIZE_STACK_SIZE
+#define CC_AT_DATA
+#else
+#define CC_AT_DATA __data
+#endif
+
 /* Generic types. */
 typedef unsigned short uip_stats_t;
 

cpu/cc253x/dev/cc2530-rf.c

@@ -107,7 +107,7 @@ static const uint8_t magic[] = { 0x53, 0x6E, 0x69, 0x66 }; /* Snif */
 #define CC2530_RF_AUTOACK 1
 #endif
 /*---------------------------------------------------------------------------*/
-static uint8_t __data rf_flags;
+static uint8_t CC_AT_DATA rf_flags;
 
 static int on(void); /* prepare() needs our prototype */
 static int off(void); /* transmit() needs our prototype */

cpu/cc253x/dev/clock.c

@@ -55,8 +55,8 @@ volatile uint8_t sleep_flag;
 /* Do NOT remove the absolute address and do NOT remove the initialiser here */
 __xdata __at(0x0000) static unsigned long timer_value = 0;
 
-static volatile __data clock_time_t count = 0; /* Uptime in ticks */
-static volatile __data clock_time_t seconds = 0; /* Uptime in secs */
+static volatile CC_AT_DATA clock_time_t count = 0; /* Uptime in ticks */
+static volatile CC_AT_DATA clock_time_t seconds = 0; /* Uptime in secs */
 /*---------------------------------------------------------------------------*/
 /**
  * Each iteration is ~1.0xy usec, so this function delays for roughly len usec
@@ -132,6 +132,11 @@ clock_init(void)
   STIE = 1; /* IEN0.STIE interrupt enable */
 }
 /*---------------------------------------------------------------------------*/
+/* avoid referencing bits, we don't call code which use them */
+#pragma save
+#if CC_CONF_OPTIMIZE_STACK_SIZE
+#pragma exclude bits
+#endif
 void
 clock_isr(void) __interrupt(ST_VECTOR)
 {
@@ -177,4 +182,5 @@ clock_isr(void) __interrupt(ST_VECTOR)
   ENERGEST_OFF(ENERGEST_TYPE_IRQ);
   ENABLE_INTERRUPTS();
 }
+#pragma restore
 /*---------------------------------------------------------------------------*/

cpu/cc253x/dev/dma_intr.c

@@ -32,6 +32,11 @@ extern void spi_rx_dma_callback(void);
  *
  * if callback defined a poll is made to that process
  */
+/* Avoid referencing bits, we don't call code which use them */
+#pragma save
+#if CC_CONF_OPTIMIZE_STACK_SIZE
+#pragma exclude bits
+#endif
 void
 dma_isr(void) __interrupt (DMA_VECTOR)
 {
@@ -65,4 +70,5 @@ dma_isr(void) __interrupt (DMA_VECTOR)
 #endif
   EA = 1;
 }
+#pragma restore
 /*---------------------------------------------------------------------------*/

cpu/cc253x/dev/uart-intr.c

@@ -33,6 +33,11 @@ uart0_set_input(int (*input)(unsigned char c))
 }
 /*---------------------------------------------------------------------------*/
 #if UART0_CONF_WITH_INPUT
+/* avoid referencing bits since we're not using them */
+#pragma save
+#if CC_CONF_OPTIMIZE_STACK_SIZE
+#pragma exclude bits
+#endif
 void
 uart0_rx_isr(void) __interrupt (URX0_VECTOR)
 {
@@ -44,6 +49,7 @@ uart0_rx_isr(void) __interrupt (URX0_VECTOR)
   }
   ENERGEST_OFF(ENERGEST_TYPE_IRQ);
 }
+#pragma restore
 #endif
 #endif /* UART0_ENABLE */
 #if UART1_ENABLE
@@ -55,6 +61,11 @@ uart1_set_input(int (*input)(unsigned char c))
 }
 /*---------------------------------------------------------------------------*/
 #if UART_ONE_CONF_WITH_INPUT
+/* avoid referencing bits since we're not using them */
+#pragma save
+#if CC_CONF_OPTIMIZE_STACK_SIZE
+#pragma exclude bits
+#endif
 void
 uart1_rx_isr(void) __interrupt (URX1_VECTOR)
 {
@@ -65,6 +76,7 @@ uart1_rx_isr(void) __interrupt (URX1_VECTOR)
   }
   ENERGEST_OFF(ENERGEST_TYPE_IRQ);
 }
+#pragma restore
 /*---------------------------------------------------------------------------*/
 #endif /* UART_ONE_CONF_WITH_INPUT */
 #endif /* UART1_ENABLE */

cpu/cc253x/rtimer-arch.c

@@ -96,6 +96,11 @@ rtimer_arch_schedule(rtimer_clock_t t)
   T1CCTL1 |= T1CCTL_IM;
 }
 /*---------------------------------------------------------------------------*/
+/* avoid referencing bits, we don't call code which use them */
+#pragma save
+#if CC_CONF_OPTIMIZE_STACK_SIZE
+#pragma exclude bits
+#endif
 void
 rtimer_isr(void) __interrupt(T1_VECTOR)
 {
@@ -111,3 +116,4 @@ rtimer_isr(void) __interrupt(T1_VECTOR)
   ENERGEST_OFF(ENERGEST_TYPE_IRQ);
   T1IE = 1; /* Acknowledge Timer 1 Interrupts */
 }
+#pragma restore