accessing immap_t * variable in mpc8260

2003-03-13 Thread Omanakuttan
Hi, We are writing existing drivers for mpc8260 FCC and writing new ones for MCC. we are unable to small (may be foolish) problem of accessing immap address registers. In FCC code, eldk/ppc_82xx/usr/src/linux/arch/ppc/8260_io/fcc_enet.c, immap_t * immap is simply typecasted to IMAP_ADDR, which

accessing immap_t * variable in mpc8260

2003-03-13 Thread Dan Malek
Omanakuttan wrote: I am confused at this point, that how can kernel code access a physical address as if it were virtual address ? how does the page frame - page conversion (and vice versa) happens on this front? There are some kernel address spaces that are mapped 1:1 virtual to physical,

accessing immap_t * variable in mpc8260

2003-03-14 Thread Paul Mackerras
Omanakuttan writes: In FCC code, eldk/ppc_82xx/usr/src/linux/arch/ppc/8260_io/fcc_enet.c, immap_t * immap is simply typecasted to IMAP_ADDR, which is ((uint)0xf000). Now, after assigning this physical address, fcc_enet code continues the immap_t variable without doing any __va macro.

accessing immap_t * variable in mpc8260

2003-03-14 Thread Omanakuttan
Thanks for the answers. Now I have a better picture, still some more doubts... Paul Mackerras wrote: Omanakuttan writes: In FCC code, eldk/ppc_82xx/usr/src/linux/arch/ppc/8260_io/fcc_enet.c, immap_t * immap is simply typecasted to IMAP_ADDR, which is ((uint)0xf000). Now, after assigning