diff options
| author | Haren Myneni <haren@linux.ibm.com> | 2020-04-17 02:02:01 -0700 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-04-20 16:53:14 +1000 |
| commit | dda44eb29c235735a5ceae283dc521cfca27885c (patch) | |
| tree | 89470b22fe9ed17e01a43bd40898760d7b6cbf9e /arch/powerpc/include/asm/vas.h | |
| parent | 45f25a79fe50f330b563d012fc856a1103cb00d8 (diff) | |
| download | linux-dda44eb29c235735a5ceae283dc521cfca27885c.tar.bz2 | |
powerpc/vas: Add VAS user space API
On power9, userspace can send GZIP compression requests directly to NX
once kernel establishes NX channel / window with VAS. This patch provides
user space API which allows user space to establish channel using open
VAS_TX_WIN_OPEN ioctl, mmap and close operations.
Each window corresponds to file descriptor and application can open
multiple windows. After the window is opened, VAS_TX_WIN_OPEN icoctl to
open a window on specific VAS instance, mmap() system call to map
the hardware address of engine's request queue into the application's
virtual address space.
Then the application can then submit one or more requests to the the
engine by using the copy/paste instructions and pasting the CRBs to
the virtual address (aka paste_address) returned by mmap().
Only NX GZIP coprocessor type is supported right now and allow GZIP
engine access via /dev/crypto/nx-gzip device node.
Thanks to Michael Ellerman for his changes and suggestions to make the
ioctl generic to support any coprocessor type.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587114121.2275.1109.camel@hbabu-laptop
Diffstat (limited to 'arch/powerpc/include/asm/vas.h')
| -rw-r--r-- | arch/powerpc/include/asm/vas.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h index f93e6b0f5c84..6e427bc29b3a 100644 --- a/arch/powerpc/include/asm/vas.h +++ b/arch/powerpc/include/asm/vas.h @@ -163,4 +163,16 @@ int vas_copy_crb(void *crb, int offset); */ int vas_paste_crb(struct vas_window *win, int offset, bool re); +/* + * Register / unregister coprocessor type to VAS API which will be exported + * to user space. Applications can use this API to open / close window + * which can be used to send / receive requests directly to cooprcessor. + * + * Only NX GZIP coprocessor type is supported now, but this API can be + * used for others in future. + */ +int vas_register_coproc_api(struct module *mod, enum vas_cop_type cop_type, + const char *name); +void vas_unregister_coproc_api(void); + #endif /* __ASM_POWERPC_VAS_H */ |