Merge pull request #12899 from benpicco/lpc2387-micropython

cpu/lpc2387: align lpc2387.ld with cortexm_base.ld, provide thread_isr_stack_*() - enables MicroPython

cpu/arm7_common/arm7_init.c

@@ -31,10 +31,10 @@ static inline void _init_data(void)
 {
     /* (linker script ensures that data is 32-bit aligned) */
     extern unsigned int _etext;
-    extern unsigned int _data;
+    extern unsigned int _srelocate; /* .data section */
-    extern unsigned int _edata;
+    extern unsigned int _erelocate;
-    extern unsigned int __bss_start;
+    extern unsigned int _szero;     /* .bss section */
-    extern unsigned int __bss_end;
+    extern unsigned int _ezero;
 
 /* Support for Battery Backup RAM */
 #ifdef CPU_HAS_BACKUP_RAM
@@ -49,18 +49,38 @@ static inline void _init_data(void)
     register unsigned int *dst;
     register unsigned int *end;
 
+#ifdef DEVELHELP
+    /* Fill user stack with canary values up until the current stack pointer */
+    /* Read current stack pointer from CPU register */
+    __asm__ volatile ("mov %[end], sp" : [end] "=r" (end) : : );
+    dst = &__stack_start;
+    while (dst < end) {
+        *(dst++) = STACK_CANARY_WORD;
+    }
+
+    /* fill the interrupt stacks with canary values */
+    extern unsigned int __stack_usr_start;
+    extern unsigned int __stack_end;
+
+    dst = &__stack_usr_start;
+    end = &__stack_end;
+    while (dst < end) {
+        *(dst++) = STACK_CANARY_WORD;
+    }
+#endif
+
     /* initialize data from flash */
     src = &_etext;
-    dst = &_data;
+    dst = &_srelocate;
-    end = &_edata;
+    end = &_erelocate;
 
     while (dst < end) {
         *dst++ = *src++;
     }
 
     /* clear bss */
-    dst = &__bss_start;
+    dst = &_szero;
-    end = &__bss_end;
+    end = &_ezero;
 
     while (dst < end) {
         *dst++ = 0;
@@ -99,9 +119,9 @@ void bootloader(void)
     _init_data();
 
 #ifdef MODULE_PUF_SRAM
-    /* uninitialized heap starts after bss section */
+    /* use uninitialized heap */
-    extern unsigned int __bss_end;
+    extern unsigned _sheap;
-    puf_sram_init((uint8_t *) __bss_end, SEED_RAM_LEN);
+    puf_sram_init((uint8_t *) &_sheap, SEED_RAM_LEN);
 #endif
 
     /* cpu specific setup of clocks, peripherals */

cpu/arm7_common/arm_cpu.c

@@ -94,3 +94,43 @@ void thread_print_stack(void)
 
     printf("STACK (%d)= %X \n", i, *s);
 }
+
+void *thread_isr_stack_start(void)
+{
+    extern uintptr_t __stack_irq_start;
+    return (void *)&__stack_irq_start;
+}
+
+void *thread_isr_stack_pointer(void)
+{
+    void *_sp;
+
+    /* If we are not in interrupt mode, the interrupt stack pointer will
+     * always point to the start of the interrupt stack.
+     */
+    if (irq_is_in()) {
+        /* read stack pointer */
+        __asm volatile ("mov %0, r13" : "=r" (_sp) );
+    } else {
+        _sp = thread_isr_stack_start();
+    }
+
+    return _sp;
+}
+
+/* This function returns the number of bytes used on the ISR stack */
+int thread_isr_stack_usage(void)
+{
+    extern uintptr_t __stack_irq_start;
+    extern uintptr_t __stack_irq_size;
+
+    uintptr_t *ptr = &__stack_irq_start - (unsigned) &__stack_irq_size;
+
+    while(((*ptr) == STACK_CANARY_WORD) && (ptr < &__stack_irq_start)) {
+        ++ptr;
+    }
+
+    ptrdiff_t num_used_words = &__stack_irq_start - ptr;
+
+    return num_used_words;
+}

cpu/arm7_common/include/arm_cpu.h

@@ -25,6 +25,16 @@ void cpu_clock_scale(uint32_t source, uint32_t target, uint32_t *prescale);
 
 void arm_reset(void);
 
+/**
+ * @brief Interrupt stack canary value
+ *
+ * @note 0xeafffffe is the ARM machine code equivalent of asm("b #0") or
+ * 'while (1);', i.e. an infinite loop.
+ * @internal
+ */
+#define STACK_CANARY_WORD   (0xEAFFFFFEu)
+
+
 #ifdef __cplusplus
 }
 #endif

cpu/lpc2387/include/cpu_conf.h

@@ -76,6 +76,14 @@ extern "C" {
  */
 #define PUF_SRAM_ATTRIBUTES __attribute__((used, section(".noinit")))
 
+/**
+ * @brief   Stack size used for the exception (ISR) stack
+ * @{
+ */
+extern unsigned __stack_irq_size;
+#define ISR_STACKSIZE                   ((unsigned) &__stack_irq_size)
+/** @} */
+
 #ifdef __cplusplus
 }
 #endif

cpu/lpc2387/ldscripts/lpc2387.ld

@@ -106,75 +106,6 @@ SECTIONS
  * RAM
  **************************************************************************/
 
-    /*
-     * collect all zero initialized sections that go into RAM
-     */
-    .bss (NOLOAD) :
-    {
-        . = ALIGN(4);                   /* ensure data is aligned so relocation can use 4-byte operations */
-        __bss_start = .;                /* define a global symbol marking the start of the .bss section */
-        *(.bss*)                        /* all .bss sections  */
-        *(COMMON)
-    } > ram                             /* put all the above in RAM (it will be cleared in the startup code */
-    . = ALIGN(4);                       /* ensure data is aligned so relocation can use 4-byte operations */
-    __bss_end = . ;                     /* define a global symbol marking the end of the .bss section */
-
-    /*
-     * collect all initialized .data sections that go into RAM
-     * initial values get placed at the end of .text in flash
-     */
-    .data :
-    {
-        . = ALIGN(4);                   /* ensure data is aligned so relocation can use 4-byte operations */
-        _data = .;                      /* create a global symbol marking the start of the .data section  */
-        *(.data .data.*)                /* all .data sections  */
-        *(.gnu.linkonce.d*)
-        . = ALIGN(4);
-        /* preinit data */
-        PROVIDE_HIDDEN (__preinit_array_start = .);
-        KEEP(*(.preinit_array))
-            PROVIDE_HIDDEN (__preinit_array_end = .);
-
-        . = ALIGN(4);
-        /* init data */
-        PROVIDE_HIDDEN (__init_array_start = .);
-        KEEP(*(SORT(.init_array.*)))
-            KEEP(*(.init_array))
-            PROVIDE_HIDDEN (__init_array_end = .);
-
-        . = ALIGN(4);
-        /* finit data */
-        PROVIDE_HIDDEN (__fini_array_start = .);
-        KEEP(*(SORT(.fini_array.*)))
-            KEEP(*(.fini_array))
-            PROVIDE_HIDDEN (__fini_array_end = .);
-    } >ram AT > rom                     /* put all the above into RAM (but load the LMA copy into FLASH) */
-    . = ALIGN(4);                       /* ensure data is aligned so relocation can use 4-byte operations */
-    _edata = .;                         /* define a global symbol marking the end of the .data section  */
-
-    /*
-     * collect all uninitialized sections that go into RAM
-     */
-    .noinit (NOLOAD) :
-    {
-        __noinit_start = .;
-        PROVIDE(__fiq_handler = .);
-        *(.fiq)
-        *(.noinit)
-    }  > ram
-    . = ALIGN(4);
-    __noinit_end = .;
-
-    _end = .;                           /* define a global symbol marking the end of application RAM */
-
-    __heap1_size = ORIGIN(ram) + LENGTH(ram) - . - __stack_size;
-    .heap1 (NOLOAD) :
-    {
-        PROVIDE(_sheap = .);
-        . = . + __heap1_size;
-        PROVIDE(_eheap = .);
-    } > ram
-
     /*
      * Stacks
      */
@@ -198,12 +129,56 @@ SECTIONS
         PROVIDE(__stack_end = .);
     } > ram
 
+    .relocate :
+    {
+        . = ALIGN(4);
+        _srelocate = .;
+        *(.ramfunc .ramfunc.*);
+        *(.data .data.*);
+        KEEP (*(.openocd .openocd.*))
+        . = ALIGN(4);
+        _erelocate = .;
+    } > ram AT> rom
+
+    /* .bss section which is used for uninitialized data */
+    .bss (NOLOAD) :
+    {
+        . = ALIGN(4);
+        _sbss = . ;
+        _szero = .;
+        *(.bss .bss.*)
+        *(COMMON)
+        . = ALIGN(4);
+        _ebss = . ;
+        _ezero = .;
+    } > ram
+
+    /*
+     * collect all uninitialized sections that go into RAM
+     */
+    .noinit (NOLOAD) :
+    {
+        __noinit_start = .;
+        PROVIDE(__fiq_handler = .);
+        *(.fiq)
+        *(.noinit)
+        . = ALIGN(4);
+        __noinit_end = .;
+    }  > ram
+
+    /* heap section */
+    . = ALIGN(4);
+    _sheap = . ;
+    _eheap = ORIGIN(ram) + LENGTH(ram);
+
+    /* Populate information about ram size */
+    _sram = ORIGIN(ram);
+    _eram = ORIGIN(ram) + LENGTH(ram);
+
     __heap2_size = LENGTH(ram_ethernet);
     .heap2 (NOLOAD) :
     {
         PROVIDE(__heap2_start = . );
-        . = . + __heap2_size;
-        PROVIDE(__heap2_max = .);       /* _heap shall always be < _heap_max */
     } > ram_ethernet
 
     . = ORIGIN(ram_usb);
@@ -216,19 +191,9 @@ SECTIONS
     {
         __heap3_size = ORIGIN(ram_usb) + LENGTH(ram_usb) - ABSOLUTE(.);
         PROVIDE(__heap3_start = . );
-        . += __heap3_size;
-        PROVIDE(__heap3_max = .);
     } > ram_usb
     __heap_size = SIZEOF(.heap3);
 
-    .backup.bss (NOLOAD) : ALIGN(4) {
-        _sbackup_bss = .;
-        *(.backup.bss)
-        _ebackup_bss = .;
-        /* Round size so that we can use 4 byte copy in init */
-        . = ALIGN(4);
-    } > ram_battery
-
     _sbackup_data_load = LOADADDR(.backup.data);
     .backup.data :  ALIGN(4) {
         _sbackup_data = .;
@@ -237,4 +202,12 @@ SECTIONS
         /* Round size so that we can use 4 byte copy in init */
         . = ALIGN(4);
     } > ram_battery AT> rom
+
+    .backup.bss (NOLOAD) : ALIGN(4) {
+        _sbackup_bss = .;
+        *(.backup.bss)
+        _ebackup_bss = .;
+        /* Round size so that we can use 4 byte copy in init */
+        . = ALIGN(4);
+    } > ram_battery
 }

pkg/micropython/Makefile.dep

@@ -5,7 +5,7 @@ USEMODULE += stdin
 FEATURES_BLACKLIST += arch_8bit arch_16bit
 
 # This port currently requires ISR_STACKSIZE and thread_isr_stack_start
-FEATURES_BLACKLIST += arch_arm7 arch_esp32 arch_esp8266 arch_riscv
+FEATURES_BLACKLIST += arch_esp32 arch_esp8266 arch_riscv
 
 # The port currently doesn't compile for mips
 FEATURES_BLACKLIST += arch_mips32r2