diff options
| author |   Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2022-04-06 02:29:24 +0300 |
|---|---|---|
| committer |   Dave Hansen <dave.hansen@linux.intel.com> | 2022-04-07 08:27:52 -0700 |
| commit | eb4ea1ae8f45e3249e7586f30be8977478202a37 (patch) | |
| tree | 5ace75b43fad2217fc8eead995690b73776bba5d /arch/x86/boot/boot.h | |
| parent | x86: Consolidate port I/O helpers (diff) | |
| download | linux-dev-eb4ea1ae8f45e3249e7586f30be8977478202a37.tar.xz linux-dev-eb4ea1ae8f45e3249e7586f30be8977478202a37.zip | |
x86/boot: Port I/O: Allow to hook up alternative helpers
Port I/O instructions trigger #VE in the TDX environment. In response to
the exception, kernel emulates these instructions using hypercalls.
But during early boot, on the decompression stage, it is cumbersome to
deal with #VE. It is cleaner to go to hypercalls directly, bypassing #VE
handling.
Add a way to hook up alternative port I/O helpers in the boot stub with
a new pio_ops structure. For now, set the ops structure to just call
the normal I/O operation functions.
out*()/in*() macros redefined to use pio_ops callbacks. It eliminates
need in changing call sites. io_delay() changed to use port I/O helper
instead of inline assembly.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20220405232939.73860-16-kirill.shutemov@linux.intel.com
Diffstat (limited to 'arch/x86/boot/boot.h')
| -rw-r--r-- | arch/x86/boot/boot.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h index 22a474c5b3e8..b42b91606ca8 100644 --- a/arch/x86/boot/boot.h +++ b/arch/x86/boot/boot.h @@ -23,10 +23,10 @@ #include <linux/edd.h> #include <asm/setup.h> #include <asm/asm.h> -#include <asm/shared/io.h> #include "bitops.h" #include "ctype.h" #include "cpuflags.h" +#include "io.h" /* Useful macros */ #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) @@ -39,7 +39,7 @@ extern struct boot_params boot_params; static inline void io_delay(void) { const u16 DELAY_PORT = 0x80; - asm volatile("outb %%al,%0" : : "dN" (DELAY_PORT)); + outb(0, DELAY_PORT); } /* These functions are used to reference data in other segments. */ |