basecmd: Move low-level alloc code into basecmd.c

Implement new dynmem_start() and dynmem_end() functions instead of
alloc_chunk() and alloc_chunks() in the board code.  This simplifies
the board code.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

6 files changed, 74 insertions, 90 deletions

diff --git a/src/avr/main.c b/src/avr/main.c
index a210300f..e3de4c03 100644
--- a/src/avr/main.c
+++ b/src/avr/main.c
@@ -5,10 +5,9 @@
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
 #include <avr/io.h> // AVR_STACK_POINTER_REG
-#include <stdlib.h> // __malloc_heap_end
-#include <string.h> // memset
 #include <util/crc16.h> // _crc_ccitt_update
 #include "autoconf.h" // CONFIG_MCU
+#include "board/misc.h" // dynmem_start
 #include "command.h" // DECL_CONSTANT
 #include "irq.h" // irq_enable
 #include "sched.h" // sched_main
@@ -17,36 +16,22 @@ DECL_CONSTANT(MCU, CONFIG_MCU);
 
 
 /****************************************************************
- * Memmory allocation
+ * Dynamic memory
  ****************************************************************/
 
-// Allocate an area of memory
+// Return the start of memory available for dynamic allocations
 void *
-alloc_chunk(size_t size)
+dynmem_start(void)
 {
-    void *data = malloc(size);
-    if (!data)
-        shutdown("alloc_chunk failed");
-    memset(data, 0, size);
-    return data;
+    extern char _end;
+    return &_end;
 }
 
-// Allocate an array of chunks
+// Return the end of memory available for dynamic allocations
 void *
-alloc_chunks(size_t size, size_t count, size_t *avail)
+dynmem_end(void)
 {
-    uint16_t memend = ALIGN(AVR_STACK_POINTER_REG, 256);
-    __malloc_heap_end = (void*)memend - CONFIG_AVR_STACK_SIZE;
-    extern char *__brkval;
-    uint16_t maxsize = __malloc_heap_end - __brkval - 2;
-    if ((int16_t)maxsize < 0)
-        maxsize = 0;
-    if (count * size > maxsize)
-        count = maxsize / size;
-    if (!count)
-        shutdown("alloc_chunks failed");
-    *avail = count;
-    return alloc_chunk(count * size);
+    return (void*)ALIGN(AVR_STACK_POINTER_REG, 256) - CONFIG_AVR_STACK_SIZE;
 }
 
 
diff --git a/src/basecmd.c b/src/basecmd.c
index 7a2f7882..da21fad0 100644
--- a/src/basecmd.c
+++ b/src/basecmd.c
@@ -4,6 +4,7 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
+#include <string.h> // memset
 #include "basecmd.h" // oid_lookup
 #include "board/irq.h" // irq_save
 #include "board/misc.h" // alloc_maxsize
@@ -13,6 +14,47 @@
 
 
 /****************************************************************
+ * Low level allocation
+ ****************************************************************/
+
+static void *alloc_end;
+
+void
+alloc_init(void)
+{
+    alloc_end = (void*)ALIGN((size_t)dynmem_start(), __alignof__(void*));
+}
+DECL_INIT(alloc_init);
+
+// Allocate an area of memory
+static void *
+alloc_chunk(size_t size)
+{
+    if (alloc_end + size > dynmem_end())
+        shutdown("alloc_chunk failed");
+    void *data = alloc_end;
+    alloc_end += ALIGN(size, __alignof__(void*));
+    memset(data, 0, size);
+    return data;
+}
+
+// Allocate an array of chunks
+static void *
+alloc_chunks(size_t size, size_t count, uint16_t *avail)
+{
+    size_t can_alloc = 0;
+    void *p = alloc_end, *end = dynmem_end();
+    while (can_alloc < count && p + size <= end)
+        can_alloc++, p += size;
+    if (!can_alloc)
+        shutdown("alloc_chunks failed");
+    void *data = alloc_chunk(p - alloc_end);
+    *avail = can_alloc;
+    return data;
+}
+
+
+/****************************************************************
  * Move queue
  ****************************************************************/
 
@@ -85,10 +127,10 @@ DECL_SHUTDOWN(move_reset);
 static void
 move_finalize(void)
 {
+    if (is_finalized())
+        shutdown("Already finalized");
     move_request_size(sizeof(*move_free_list));
-    size_t count;
-    move_list = alloc_chunks(move_item_size, 1024, &count);
-    move_count = count;
+    move_list = alloc_chunks(move_item_size, 1024, &move_count);
     move_reset();
 }
 
@@ -167,8 +209,6 @@ DECL_COMMAND_FLAGS(command_get_config, HF_IN_SHUTDOWN, "get_config");
 void
 command_finalize_config(uint32_t *args)
 {
-    if (!oids || is_finalized())
-        shutdown("Can't finalize");
     move_finalize();
     config_crc = args[0];
     command_get_config(NULL);
diff --git a/src/generic/alloc.c b/src/generic/alloc.c
index 37de4d6a..1ff75113 100644
--- a/src/generic/alloc.c
+++ b/src/generic/alloc.c
@@ -1,37 +1,23 @@
-// Dummy implementation for alloc commands
+// Generic implementation of dynamic memory pool
 //
 // Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include <stdlib.h> // malloc
-#include <string.h> // memset
-#include "command.h" // shutdown
-#include "misc.h" // alloc_chunk
-#include "sched.h" // sched_shutdown
+#include "misc.h" // dynmem_start
 
-// Return the maximum allocation size that can succeed up to 'reqsize'
-size_t
-alloc_chunk_maxsize(size_t reqsize)
-{
-    return reqsize;
-}
+static char dynmem_pool[20 * 1024];
 
-// Allocate an area of memory
+// Return the start of memory available for dynamic allocations
 void *
-alloc_chunk(size_t size)
+dynmem_start(void)
 {
-    void *data = malloc(size);
-    if (!data)
-        shutdown("alloc_chunk failed");
-    memset(data, 0, size);
-    return data;
+    return dynmem_pool;
 }
 
-// Allocate an array of chunks
+// Return the end of memory available for dynamic allocations
 void *
-alloc_chunks(size_t size, size_t count, size_t *avail)
+dynmem_end(void)
 {
-    *avail = count;
-    return alloc_chunk(size * count);
+    return &dynmem_pool[sizeof(dynmem_pool)];
 }
diff --git a/src/generic/misc.h b/src/generic/misc.h
index 960eb6a2..b2f1c050 100644
--- a/src/generic/misc.h
+++ b/src/generic/misc.h
@@ -13,8 +13,8 @@ uint8_t timer_is_before(uint32_t time1, uint32_t time2);
 uint32_t timer_read_time(void);
 void timer_periodic(void);
 
-void *alloc_chunk(size_t size);
-void *alloc_chunks(size_t size, size_t count, size_t *avail);
+void *dynmem_start(void);
+void *dynmem_end(void);
 
 uint16_t crc16_ccitt(char *buf, uint8_t len);
 
diff --git a/src/pru/main.c b/src/pru/main.c
index 021bee3f..a95bde1b 100644
--- a/src/pru/main.c
+++ b/src/pru/main.c
@@ -5,12 +5,11 @@
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
 #include <stdint.h> // uint32_t
-#include <string.h> // memset
 #include <pru/io.h> // read_r31
 #include <pru_iep.h> // CT_IEP
 #include <pru_intc.h> // CT_INTC
 #include <rsc_types.h> // resource_table
-#include "board/misc.h" // alloc_chunk
+#include "board/misc.h" // dynmem_start
 #include "board/io.h" // readl
 #include "board/irq.h" // irq_disable
 #include "command.h" // shutdown
@@ -175,39 +174,24 @@ const struct command_parser shutdown_request = {
 
 
 /****************************************************************
- * Allocator
+ * Dynamic memory
  ****************************************************************/
 
-extern char _heap_start;
-static void *heap_ptr = &_heap_start;
-
 #define STACK_SIZE 256
-#define END_MEM ((void*)(8*1024 - STACK_SIZE))
 
-// Allocate an area of memory
+// Return the start of memory available for dynamic allocations
 void *
-alloc_chunk(size_t size)
+dynmem_start(void)
 {
-    if (heap_ptr + size > END_MEM)
-        shutdown("alloc_chunk failed");
-    void *data = heap_ptr;
-    heap_ptr += size;
-    memset(data, 0, size);
-    return data;
+    extern char _heap_start;
+    return &_heap_start;
 }
 
-// Allocate an array of chunks
+// Return the end of memory available for dynamic allocations
 void *
-alloc_chunks(size_t size, size_t count, size_t *avail)
+dynmem_end(void)
 {
-    size_t can_alloc = 0;
-    void *p = heap_ptr;
-    for (; can_alloc <= count && p + size <= END_MEM; can_alloc++, p += size)
-        ;
-    if (!can_alloc)
-        shutdown("alloc_chunks failed");
-    *avail = can_alloc;
-    return alloc_chunk(size * can_alloc);
+    return (void*)(8*1024 - STACK_SIZE);
 }
 
 
diff --git a/src/sam3x8e/main.c b/src/sam3x8e/main.c
index 63c27cd7..e8bd30ba 100644
--- a/src/sam3x8e/main.c
+++ b/src/sam3x8e/main.c
@@ -4,7 +4,6 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include "board/misc.h" // alloc_maxsize
 #include "command.h" // DECL_CONSTANT
 #include "sam3x8e.h" // WDT
 #include "sched.h" // sched_main
@@ -43,16 +42,6 @@ command_reset(uint32_t *args)
 }
 DECL_COMMAND_FLAGS(command_reset, HF_IN_SHUTDOWN, "reset");
 
-void * __visible
-_sbrk(int nbytes)
-{
-    extern char _end;
-    static void *heap_ptr = (void *)&_end;
-    void *pos = heap_ptr;
-    heap_ptr = pos + nbytes;
-    return pos;
-}
-
 // Main entry point
 int
 main(void)