hw/pci-host/pam: Replace magic number by PAM_REGIONS_COUNT definition

While this change helps triskaidekaphobic developers, it
is a good practice to avoid magic values and using constant
definitions instead.

Introduce the PAM_REGIONS_COUNT and use it. No logical change.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Julia Suvorova <jusual@redhat.com>
Message-Id: <20201202132038.1276404-1-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

hw/pci-host/pam.c

@@ -62,7 +62,7 @@ void init_pam(DeviceState *dev, MemoryRegion *ram_memory,
 
 void pam_update(PAMMemoryRegion *pam, int idx, uint8_t val)
 {
-    assert(0 <= idx && idx <= 12);
+    assert(0 <= idx && idx < PAM_REGIONS_COUNT);
 
     memory_region_set_enabled(&pam->alias[pam->current], false);
     pam->current = (val >> ((!(idx & 1)) * 4)) & PAM_ATTR_MASK;

hw/pci-host/q35.c

@@ -641,7 +641,7 @@ static void mch_realize(PCIDevice *d, Error **errp)
     init_pam(DEVICE(mch), mch->ram_memory, mch->system_memory,
              mch->pci_address_space, &mch->pam_regions[0],
              PAM_BIOS_BASE, PAM_BIOS_SIZE);
-    for (i = 0; i < 12; ++i) {
+    for (i = 0; i < ARRAY_SIZE(mch->pam_regions) - 1; ++i) {
         init_pam(DEVICE(mch), mch->ram_memory, mch->system_memory,
                  mch->pci_address_space, &mch->pam_regions[i+1],
                  PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE, PAM_EXPAN_SIZE);

include/hw/pci-host/i440fx.h

@@ -29,7 +29,7 @@ struct PCII440FXState {
     MemoryRegion *system_memory;
     MemoryRegion *pci_address_space;
     MemoryRegion *ram_memory;
-    PAMMemoryRegion pam_regions[13];
+    PAMMemoryRegion pam_regions[PAM_REGIONS_COUNT];
     MemoryRegion smram_region;
     MemoryRegion smram, low_smram;
 };

include/hw/pci-host/pam.h

@@ -80,6 +80,8 @@
 #define SMRAM_C_BASE_SEG_MASK  ((uint8_t)0x7)
 #define SMRAM_C_BASE_SEG       ((uint8_t)0x2)  /* hardwired to b010 */
 
+#define PAM_REGIONS_COUNT       13
+
 typedef struct PAMMemoryRegion {
     MemoryRegion alias[4];  /* index = PAM value */
     unsigned current;

include/hw/pci-host/q35.h

@@ -44,7 +44,7 @@ struct MCHPCIState {
     MemoryRegion *pci_address_space;
     MemoryRegion *system_memory;
     MemoryRegion *address_space_io;
-    PAMMemoryRegion pam_regions[13];
+    PAMMemoryRegion pam_regions[PAM_REGIONS_COUNT];
     MemoryRegion smram_region, open_high_smram;
     MemoryRegion smram, low_smram, high_smram;
     MemoryRegion tseg_blackhole, tseg_window;