treewide: Consolidate Apple DMI checks

We're about to amend ACPI bus scan with DMI checks whether we're running
on a Mac to support Apple device properties in AML.  The DMI checks are
performed for every single device, adding overhead for everything x86
that isn't Apple, which is the majority.  Rafael and Andy therefore
request to perform the DMI match only once and cache the result.

Outside of ACPI various other Apple DMI checks exist and it seems
reasonable to use the cached value there as well.  Rafael, Andy and
Darren suggest performing the DMI check in arch code and making it
available with a header in include/linux/platform_data/x86/.

To this end, add early_platform_quirks() to arch/x86/kernel/quirks.c
to perform the DMI check and invoke it from setup_arch().  Switch over
all existing Apple DMI checks, thereby fixing two deficiencies:

* They are now #defined to false on non-x86 arches and can thus be
  optimized away if they're located in cross-arch code.

* Some of them only match "Apple Inc." but not "Apple Computer, Inc.",
  which is used by BIOSes released between January 2006 (when the first
  x86 Macs started shipping) and January 2007 (when the company name
  changed upon introduction of the iPhone).

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Suggested-by: Darren Hart <dvhart@infradead.org>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2 files changed, 6 insertions, 11 deletions

diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index 8ee340290219..17eba072e1ed 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -13,9 +13,9 @@
  */
 
 #include <linux/delay.h>
-#include <linux/dmi.h>
 #include <linux/mutex.h>
 #include <linux/pci.h>
+#include <linux/platform_data/x86/apple.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
@@ -102,11 +102,6 @@ static inline u64 get_route(u32 route_hi, u32 route_lo)
         return (u64)route_hi << 32 | route_lo;
 }
 
-static inline bool is_apple(void)
-{
-        return dmi_match(DMI_BOARD_VENDOR, "Apple Inc.");
-}
-
 static bool icm_match(const struct tb_cfg_request *req,
                       const struct ctl_pkg *pkg)
 {
@@ -176,7 +171,7 @@ static int icm_request(struct tb *tb, const void *request, size_t request_size,
 
 static bool icm_fr_is_supported(struct tb *tb)
 {
-        return !is_apple();
+        return !x86_apple_machine;
 }
 
 static inline int icm_fr_get_switch_index(u32 port)
@@ -517,7 +512,7 @@ static bool icm_ar_is_supported(struct tb *tb)
          * Starting from Alpine Ridge we can use ICM on Apple machines
          * as well. We just need to reset and re-enable it first.
          */
-        if (!is_apple())
+        if (!x86_apple_machine)
                 return true;
 
         /*
@@ -1004,7 +999,7 @@ static int icm_start(struct tb *tb)
          * don't provide images publicly either. To be on the safe side
          * prevent root switch NVM upgrade on Macs for now.
          */
-        tb->root_switch->no_nvm_upgrade = is_apple();
+        tb->root_switch->no_nvm_upgrade = x86_apple_machine;
 
         ret = tb_switch_add(tb->root_switch);
         if (ret)
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 1b02ca0b6129..0b22ad9d68b4 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -7,7 +7,7 @@
 #include <linux/slab.h>
 #include <linux/errno.h>
 #include <linux/delay.h>
-#include <linux/dmi.h>
+#include <linux/platform_data/x86/apple.h>
 
 #include "tb.h"
 #include "tb_regs.h"
@@ -453,7 +453,7 @@ struct tb *tb_probe(struct tb_nhi *nhi)
         struct tb_cm *tcm;
         struct tb *tb;
 
-        if (!dmi_match(DMI_BOARD_VENDOR, "Apple Inc."))
+        if (!x86_apple_machine)
                 return NULL;
 
         tb = tb_domain_alloc(nhi, sizeof(*tcm));