x86, intel_txt: Factor out the code for S3 setup

S3 sleep requires special setup in tboot.  However, the data
structures needed to do such setup are only available if
CONFIG_ACPI_SLEEP is enabled.  Abstract them out as much as possible,
so we can have a single tboot_setup_sleep() which either is a proper
implementation or a stub which simply calls BUG().

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Shane Wang <shane.wang@intel.com>
Cc: Joseph Cihula <joseph.cihula@intel.com>

1 files changed, 40 insertions, 13 deletions

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 1ab801208945..a183beffe39e 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -34,6 +34,7 @@
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
 #include <asm/fixmap.h>
+#include <asm/proto.h>
 #include <asm/setup.h>
 #include <asm/tboot.h>
 #include <asm/e820.h>
@@ -164,25 +165,51 @@ void tboot_create_trampoline(void)
         map_base = PFN_DOWN(tboot->tboot_base);
         map_size = PFN_UP(tboot->tboot_size);
         if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
-                panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n", map_base, map_size);
+                panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n",
+                      map_base, map_size);
 }
 
-static void set_mac_regions(void)
+#ifdef CONFIG_ACPI_SLEEP
+
+static void add_mac_region(phys_addr_t start, unsigned long size)
 {
-        tboot->num_mac_regions = 3;
+        struct tboot_mac_region *mr;
+        phys_addr_t end = start + size;
+
+        if (start && size) {
+                mr = &tboot->mac_regions[tboot->num_mac_regions++];
+                mr->start = round_down(start, PAGE_SIZE);
+                mr->size  = round_up(end, PAGE_SIZE) - mr->start;
+        }
+}
+
+static int tboot_setup_sleep(void)
+{
+        tboot->num_mac_regions = 0;
+
         /* S3 resume code */
-        tboot->mac_regions[0].start = PFN_PHYS(PFN_DOWN(acpi_wakeup_address));
-        tboot->mac_regions[0].size = PFN_UP(WAKEUP_SIZE) << PAGE_SHIFT;
+        add_mac_region(acpi_wakeup_address, WAKEUP_SIZE);
         /* AP trampoline code */
-        tboot->mac_regions[1].start =
-                        PFN_PHYS(PFN_DOWN(virt_to_phys(trampoline_base)));
-        tboot->mac_regions[1].size = PFN_UP(TRAMPOLINE_SIZE) << PAGE_SHIFT;
+        add_mac_region(virt_to_phys(trampoline_base), TRAMPOLINE_SIZE);
         /* kernel code + data + bss */
-        tboot->mac_regions[2].start = PFN_PHYS(PFN_DOWN(virt_to_phys(&_text)));
-        tboot->mac_regions[2].size = PFN_PHYS(PFN_UP(virt_to_phys(&_end))) -
-                                     PFN_PHYS(PFN_DOWN(virt_to_phys(&_text)));
+        add_mac_region(virt_to_phys(_text), _end - _text);
+
+        tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address;
+
+        return 0;
 }
 
+#else /* no CONFIG_ACPI_SLEEP */
+
+static int tboot_setup_sleep(void)
+{
+        /* S3 shutdown requested, but S3 not supported by the kernel... */
+        BUG();
+        return -1;
+}
+
+#endif
+
 void tboot_shutdown(u32 shutdown_type)
 {
         void (*shutdown)(void);
@@ -200,7 +227,8 @@ void tboot_shutdown(u32 shutdown_type)
 
         /* if this is S3 then set regions to MAC */
         if (shutdown_type == TB_SHUTDOWN_S3)
-                set_mac_regions();
+                if (tboot_setup_sleep())
+                        return;
 
         tboot->shutdown_type = shutdown_type;
 
@@ -253,7 +281,6 @@ void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
         tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control;
         /* we always use the 32b wakeup vector */
         tboot->acpi_sinfo.vector_width = 32;
-        tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address;
 
         if (sleep_state >= ACPI_S_STATE_COUNT ||
             acpi_shutdown_map[sleep_state] == -1) {