diff options
| author | Ian Moffett <ian@osmora.org> | 2024-03-13 21:27:39 -0400 |
|---|---|---|
| committer | Ian Moffett <ian@osmora.org> | 2024-03-13 21:48:21 -0400 |
| commit | fc9c7bab5bb64dd2242e9e9dff98060d64af2a32 (patch) | |
| tree | 7595e81043217c2e6ba81fe1cec5850bf7ae77b7 | |
| parent | 8b68f956154b43b2b2fe2b8783ae6f23bf90d47b (diff) | |
kernel/amd64: machdep: Add pcb init code
This commit adds a processor specific routine which sets up the
Process Control Block for a thread
Signed-off-by: Ian Moffett <ian@osmora.org>
| -rw-r--r-- | sys/arch/amd64/amd64/machdep.c | 25 | ||||
| -rw-r--r-- | sys/include/sys/machdep.h | 2 | ||||
| -rw-r--r-- | sys/kern/kern_sched.c | 2 |
3 files changed, 29 insertions, 0 deletions
diff --git a/sys/arch/amd64/amd64/machdep.c b/sys/arch/amd64/amd64/machdep.c index 809e395..0789f5a 100644 --- a/sys/arch/amd64/amd64/machdep.c +++ b/sys/arch/amd64/amd64/machdep.c @@ -154,6 +154,31 @@ intr_unmask(void) __ASMV("sti"); } +int +processor_init_pcb(struct proc *proc) +{ + struct pcb *pcb = &proc->pcb; + const uint16_t FPU_FCW = 0x33F; + const uint32_t SSE_MXCSR = 0x1F80; + + /* Allocate FPU save area, aligned on a 16 byte boundary */ + pcb->fpu_state = PHYS_TO_VIRT(vm_alloc_pageframe(1)); + if (pcb->fpu_state == 0) { + return -1; + } + + /* + * Setup x87 FPU control word and SSE MXCSR bits + * as per the sysv ABI + */ + __ASMV("fldcw %0\n" + "ldmxcsr %1" + :: "m" (FPU_FCW), + "m" (SSE_MXCSR) : "memory"); + + amd64_fxsave(pcb->fpu_state); + return 0; +} void processor_init(void) { diff --git a/sys/include/sys/machdep.h b/sys/include/sys/machdep.h index 713b7db..151d5f8 100644 --- a/sys/include/sys/machdep.h +++ b/sys/include/sys/machdep.h @@ -32,11 +32,13 @@ #include <sys/types.h> #include <sys/cdefs.h> +#include <sys/proc.h> #if defined(_KERNEL) #define MAXCPUS 32 +int processor_init_pcb(struct proc *proc); void processor_init(void); void processor_halt(void); void intr_mask(void); diff --git a/sys/kern/kern_sched.c b/sys/kern/kern_sched.c index 7be8241..f8f09c4 100644 --- a/sys/kern/kern_sched.c +++ b/sys/kern/kern_sched.c @@ -36,6 +36,7 @@ #include <sys/spinlock.h> #include <sys/loader.h> #include <sys/panic.h> +#include <sys/machdep.h> #include <fs/initramfs.h> #include <vm/dynalloc.h> #include <vm/physseg.h> @@ -264,6 +265,7 @@ sched_create_td(uintptr_t rip, char *argvp[], char *envp[], struct auxval auxv, td->cpu = NULL; /* Not yet assigned a core */ td->tf = tf; td->addrsp = vas; + processor_init_pcb(td); /* Setup trapframe */ if (!is_user) { |