diff options
Diffstat (limited to 'physmap.c')
-rw-r--r-- | physmap.c | 65 |
1 files changed, 33 insertions, 32 deletions
@@ -30,66 +30,67 @@ #ifdef __DJGPP__ #include <dpmi.h> +#include <sys/nearptr.h> #define MEM_DEV "dpmi" -unsigned short segFS = 0; +static void *realmem_map; -void *sys_physmap(unsigned long phys_addr, size_t len) +static void *map_first_meg(unsigned long phys_addr, size_t len) { - int ret; - __dpmi_meminfo mi; - if (segFS == 0) { - segFS = __dpmi_allocate_ldt_descriptors (1); - __dpmi_set_segment_base_address (segFS, 0x0); - __dpmi_set_segment_limit (segFS, 0xffffffff); + if (realmem_map) { + return realmem_map + phys_addr; } - mi.address = phys_addr; - mi.size = len; - ret = __dpmi_physical_address_mapping (&mi); + realmem_map = valloc(1024 * 1024); - if (ret != 0) { + if (!realmem_map) { return NULL; } - return (void *) mi.address; -} - -#define sys_physmap_rw_uncached sys_physmap - -#include <sys/movedata.h> -#include <sys/segments.h> -#include <go32.h> + if (__djgpp_map_physical_memory(realmem_map, (1024 * 1024), 0)) { + return NULL; + } -static void *realmem_cpy; + return realmem_map + phys_addr; +} -void *sys_physmap_ro_cached(unsigned long phys_addr, size_t len) +void *sys_physmap(unsigned long phys_addr, size_t len) { - /* no support for not a 1MB of mem */ - if ((phys_addr + len) > 1024*1024) + int ret; + __dpmi_meminfo mi; + + /* enable 4GB limit on DS descriptor */ + if (!__djgpp_nearptr_enable()) { return NULL; + } - if (realmem_cpy) - return realmem_cpy + phys_addr; + if ((phys_addr + len - 1) < (1024 * 1024)) { + /* we need to use another method to map first 1MB */ + return map_first_meg(phys_addr, len); + } - realmem_cpy = valloc(1024*1024); + mi.address = phys_addr; + mi.size = len; + ret = __dpmi_physical_address_mapping (&mi); - if (!realmem_cpy) + if (ret != 0) { return NULL; + } - movedata(_dos_ds, 0, _my_ds(), (unsigned long) realmem_cpy, 1024*1024); - return realmem_cpy + phys_addr; + return (void *) mi.address + __djgpp_conventional_base; } +#define sys_physmap_rw_uncached sys_physmap +#define sys_physmap_ro_cached sys_physmap void physunmap(void *virt_addr, size_t len) { __dpmi_meminfo mi; - /* we ignore unmaps for our cheat 1MB copy */ - if ((virt_addr >= realmem_cpy) && ((virt_addr + len) <= (realmem_cpy + 1024*1024))) { + /* we ignore unmaps for our first 1MB */ + if ((virt_addr >= realmem_map) && ((virt_addr + len) <= (realmem_map + (1024 * 1024)))) { return; } |