A cure for insomnia

Our qemu tree has finally made itself really useful. By running the Treo's bootloader inside it I was able to figure out how to get suspend to ram working properly. It turns out to be really easy, all you have to do is set PSPR to some non-zero value and put the code you want to run on resume at 0xa000000.

Also after a lot of messing with qemu, Sergey Lapin and I also figured out how to resume Zire 72. Probably. It's untested on a physical device yet. On going to sleep you need to point PSPR at the physical address of the structure below. Set resume_addr to the argument passed into pxa_ll_pm_suspend(). It may be the same or similar for other devices with the "SmallROM" bootloader (such as T3).

static struct {                                                                                                                                                                       
        u32 magic0;             /* 0x0 */                                                                                                                                             
        u32 magic1;             /* 0x4 */                                                                                                                                             
        u32 resume_addr;        /* 0x8 */                                                                                                                                             
        u32 pad[11];            /* 0xc..0x37 */                                                                                                                                       
                                                                                                                                                                                      
        /* bootloader will configure co-processor 15 with these values: */
        u32 arm_control;        /* 0x38 */                                                                                                                                            
        u32 aux_control;        /* 0x3c */                                                                                                                                            
        u32 ttb;                /* 0x40 */                                                                                                                                            
        u32 domain_access;      /* 0x44 */                                                                                                                                            
        u32 process_id;         /* 0x48 */                                                                                                                                            
} palmz72_resume_info = {                                                                                                                                                             
        .magic0 = 0xb4e6,                                                                                                                                                             
        .magic1 = 1,                                                                                                                                                                  
                                                                                                                                                                                      
        /* reset state, MMU off etc */                                                                                                                                                
        .arm_control = 0,                                                                                                                                                             
        .aux_control = 0,                                                                                                                                                             
        .ttb = 0,                                                                                                                                                                     
        .domain_access = 0,                                                                                                                                                           
        .process_id = 0,                                                                                                                                                              
};