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		f7795e4096
		
	
	
	
	
		
			
			Description copied from Linux kernel commit from Gustavo A. R. Silva
(see [3]):
--v-- description start --v--
  The current codebase makes use of the zero-length array language
  extension to the C90 standard, but the preferred mechanism to
  declare variable-length types such as these ones is a flexible
  array member [1], introduced in C99:
  struct foo {
      int stuff;
      struct boo array[];
  };
  By making use of the mechanism above, we will get a compiler
  warning in case the flexible array does not occur last in the
  structure, which will help us prevent some kind of undefined
  behavior bugs from being unadvertenly introduced [2] to the
  Linux codebase from now on.
--^-- description end --^--
Do the similar housekeeping in the QEMU codebase (which uses
C99 since commit 7be41675f7).
All these instances of code were found with the help of the
following Coccinelle script:
  @@
  identifier s, m, a;
  type t, T;
  @@
   struct s {
      ...
      t m;
  -   T a[0];
  +   T a[];
  };
  @@
  identifier s, m, a;
  type t, T;
  @@
   struct s {
      ...
      t m;
  -   T a[0];
  +   T a[];
   } QEMU_PACKED;
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76497732932f
[3] https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=17642a2fbd2c1
Inspired-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
		
	
			
		
			
				
	
	
		
			164 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			164 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * TI OMAP L4 interconnect emulation.
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|  *
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|  * Copyright (C) 2007-2009 Nokia Corporation
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|  * Written by Andrzej Zaborowski <andrew@openedhand.com>
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License as
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|  * published by the Free Software Foundation; either version 2 or
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|  * (at your option) any later version of the License.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License along
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|  * with this program; if not, see <http://www.gnu.org/licenses/>.
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|  */
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| #include "qemu/osdep.h"
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| #include "hw/arm/omap.h"
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| 
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| struct omap_l4_s {
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|     MemoryRegion *address_space;
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|     hwaddr base;
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|     int ta_num;
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|     struct omap_target_agent_s ta[];
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| };
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| 
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| struct omap_l4_s *omap_l4_init(MemoryRegion *address_space,
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|                                hwaddr base, int ta_num)
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| {
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|     struct omap_l4_s *bus = g_malloc0(
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|                     sizeof(*bus) + ta_num * sizeof(*bus->ta));
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| 
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|     bus->address_space = address_space;
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|     bus->ta_num = ta_num;
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|     bus->base = base;
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| 
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|     return bus;
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| }
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| 
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| hwaddr omap_l4_region_base(struct omap_target_agent_s *ta,
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|                                        int region)
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| {
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|     return ta->bus->base + ta->start[region].offset;
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| }
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| 
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| hwaddr omap_l4_region_size(struct omap_target_agent_s *ta,
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|                                        int region)
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| {
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|     return ta->start[region].size;
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| }
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| 
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| static uint64_t omap_l4ta_read(void *opaque, hwaddr addr,
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|                                unsigned size)
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| {
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|     struct omap_target_agent_s *s = (struct omap_target_agent_s *) opaque;
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| 
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|     if (size != 2) {
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|         return omap_badwidth_read16(opaque, addr);
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|     }
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| 
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|     switch (addr) {
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|     case 0x00:	/* COMPONENT */
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|         return s->component;
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| 
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|     case 0x20:	/* AGENT_CONTROL */
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|         return s->control;
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| 
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|     case 0x28:	/* AGENT_STATUS */
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|         return s->status;
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|     }
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| 
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|     OMAP_BAD_REG(addr);
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|     return 0;
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| }
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| 
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| static void omap_l4ta_write(void *opaque, hwaddr addr,
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|                             uint64_t value, unsigned size)
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| {
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|     struct omap_target_agent_s *s = (struct omap_target_agent_s *) opaque;
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| 
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|     if (size != 4) {
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|         omap_badwidth_write32(opaque, addr, value);
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|         return;
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|     }
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| 
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|     switch (addr) {
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|     case 0x00:	/* COMPONENT */
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|     case 0x28:	/* AGENT_STATUS */
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|         OMAP_RO_REG(addr);
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|         break;
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| 
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|     case 0x20:	/* AGENT_CONTROL */
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|         s->control = value & 0x01000700;
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|         if (value & 1)					/* OCP_RESET */
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|             s->status &= ~1;				/* REQ_TIMEOUT */
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|         break;
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| 
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|     default:
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|         OMAP_BAD_REG(addr);
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|     }
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| }
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| 
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| static const MemoryRegionOps omap_l4ta_ops = {
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|     .read = omap_l4ta_read,
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|     .write = omap_l4ta_write,
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|     .endianness = DEVICE_NATIVE_ENDIAN,
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| };
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| 
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| struct omap_target_agent_s *omap_l4ta_get(struct omap_l4_s *bus,
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|         const struct omap_l4_region_s *regions,
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|         const struct omap_l4_agent_info_s *agents,
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|         int cs)
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| {
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|     int i;
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|     struct omap_target_agent_s *ta = NULL;
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|     const struct omap_l4_agent_info_s *info = NULL;
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| 
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|     for (i = 0; i < bus->ta_num; i ++)
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|         if (agents[i].ta == cs) {
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|             ta = &bus->ta[i];
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|             info = &agents[i];
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|             break;
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|         }
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|     if (!ta) {
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|         fprintf(stderr, "%s: bad target agent (%i)\n", __func__, cs);
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|         exit(-1);
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|     }
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| 
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|     ta->bus = bus;
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|     ta->start = ®ions[info->region];
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|     ta->regions = info->regions;
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| 
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|     ta->component = ('Q' << 24) | ('E' << 16) | ('M' << 8) | ('U' << 0);
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|     ta->status = 0x00000000;
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|     ta->control = 0x00000200;	/* XXX 01000200 for L4TAO */
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| 
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|     memory_region_init_io(&ta->iomem, NULL, &omap_l4ta_ops, ta, "omap.l4ta",
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|                           omap_l4_region_size(ta, info->ta_region));
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|     omap_l4_attach(ta, info->ta_region, &ta->iomem);
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| 
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|     return ta;
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| }
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| 
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| hwaddr omap_l4_attach(struct omap_target_agent_s *ta,
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|                                          int region, MemoryRegion *mr)
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| {
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|     hwaddr base;
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| 
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|     if (region < 0 || region >= ta->regions) {
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|         fprintf(stderr, "%s: bad io region (%i)\n", __func__, region);
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|         exit(-1);
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|     }
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| 
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|     base = ta->bus->base + ta->start[region].offset;
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|     if (mr) {
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|         memory_region_add_subregion(ta->bus->address_space, base, mr);
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|     }
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| 
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|     return base;
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| }
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