Consolidate reset API, add generic reset_prepare mechanism

There are many good reasons why we may want to run some sort of generic
callback before we're executing a reset. Unfortunateley, that is really
hard right now: code that wants to reset simply calls the hard_reset()
function (or one of its ill-differentiated cousins) which is directly
implemented by a myriad of different mainboards, northbridges, SoCs,
etc. More recent x86 SoCs have tried to solve the problem in their own
little corner of soc/intel/common, but it's really something that would
benefit all of coreboot.

This patch expands the concept onto all boards: hard_reset() and friends
get implemented in a generic location where they can run hooks before
calling the platform-specific implementation that is now called
do_hard_reset(). The existing Intel reset_prepare() gets generalized as
soc_reset_prepare() (and other hooks for arch, mainboard, etc. can now
easily be added later if necessary). We will also use this central point
to ensure all platforms flush their cache before reset, which is
generally useful for all cases where we're trying to persist information
in RAM across reboots (like the new persistent CBMEM console does).

Also remove cpu_reset() completely since it's not used anywhere and
doesn't seem very useful compared to the others.

Change-Id: I41b89ce4a923102f0748922496e1dd9bce8a610f
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/19789
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

13 files changed, 13 insertions, 30 deletions

diff --git a/src/mainboard/google/foster/reset.c b/src/mainboard/google/foster/reset.c
index df16b78dae..1b9e9e9a36 100644
--- a/src/mainboard/google/foster/reset.c
+++ b/src/mainboard/google/foster/reset.c
@@ -18,8 +18,7 @@
 #include <gpio.h>
 #include <reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	gpio_output(GPIO(I5), 0);
-	while(1);
 }
diff --git a/src/mainboard/google/gale/reset.c b/src/mainboard/google/gale/reset.c
index d37051a9cb..23d83bfdf3 100644
--- a/src/mainboard/google/gale/reset.c
+++ b/src/mainboard/google/gale/reset.c
@@ -19,7 +19,7 @@
 #include <soc/iomap.h>
 #include <reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	/*
 	 * At boot time the boot loaders would have set a magic cookie
diff --git a/src/mainboard/google/gru/reset.c b/src/mainboard/google/gru/reset.c
index bd06923532..0311d587c6 100644
--- a/src/mainboard/google/gru/reset.c
+++ b/src/mainboard/google/gru/reset.c
@@ -18,9 +18,7 @@
 
 #include "board.h"
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	gpio_output(GPIO_RESET, 1);
-	while (1)
-		;
 }
diff --git a/src/mainboard/google/nyan/reset.c b/src/mainboard/google/nyan/reset.c
index 9612d56b3c..ee36292f70 100644
--- a/src/mainboard/google/nyan/reset.c
+++ b/src/mainboard/google/nyan/reset.c
@@ -17,8 +17,7 @@
 #include <gpio.h>
 #include <reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
         gpio_output(GPIO(I5), 0);
-        while(1);
 }
diff --git a/src/mainboard/google/nyan_big/reset.c b/src/mainboard/google/nyan_big/reset.c
index 9612d56b3c..ee36292f70 100644
--- a/src/mainboard/google/nyan_big/reset.c
+++ b/src/mainboard/google/nyan_big/reset.c
@@ -17,8 +17,7 @@
 #include <gpio.h>
 #include <reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
         gpio_output(GPIO(I5), 0);
-        while(1);
 }
diff --git a/src/mainboard/google/nyan_blaze/reset.c b/src/mainboard/google/nyan_blaze/reset.c
index 9612d56b3c..ee36292f70 100644
--- a/src/mainboard/google/nyan_blaze/reset.c
+++ b/src/mainboard/google/nyan_blaze/reset.c
@@ -17,8 +17,7 @@
 #include <gpio.h>
 #include <reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
         gpio_output(GPIO(I5), 0);
-        while(1);
 }
diff --git a/src/mainboard/google/purin/reset.c b/src/mainboard/google/purin/reset.c
index 5497175022..3667bbfa07 100644
--- a/src/mainboard/google/purin/reset.c
+++ b/src/mainboard/google/purin/reset.c
@@ -15,8 +15,6 @@
 
 #include <reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
-	while (1)
-		;
 }
diff --git a/src/mainboard/google/rotor/reset.c b/src/mainboard/google/rotor/reset.c
index 37c2db7c19..fc97f2df68 100644
--- a/src/mainboard/google/rotor/reset.c
+++ b/src/mainboard/google/rotor/reset.c
@@ -16,7 +16,7 @@
 #include <reset.h>
 #include <soc/reset.h>
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	mvmap2315_reset();
 }
diff --git a/src/mainboard/google/smaug/reset.c b/src/mainboard/google/smaug/reset.c
index f87582901a..fc9a0b6214 100644
--- a/src/mainboard/google/smaug/reset.c
+++ b/src/mainboard/google/smaug/reset.c
@@ -18,9 +18,7 @@
 
 #include "gpio.h"
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	gpio_output(AP_SYS_RESET_L, 0);
-	while (1)
-		;
 }
diff --git a/src/mainboard/google/storm/reset.c b/src/mainboard/google/storm/reset.c
index 94dcd4befd..d8f25274b1 100644
--- a/src/mainboard/google/storm/reset.c
+++ b/src/mainboard/google/storm/reset.c
@@ -37,12 +37,9 @@ static void wdog_reset(void)
 	write32(APCS_WDT0_BITE_TIME, RESET_WDT_BITE_TIME);
 	write32(APCS_WDT0_EN, 1);
 	write32(APCS_WDT0_CPU0_WDOG_EXPIRED_ENABLE, 1);
-
-	for (;;)
-		;
 }
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	wdog_reset();
 }
diff --git a/src/mainboard/google/veyron/reset.c b/src/mainboard/google/veyron/reset.c
index 0d11e76f70..a937aff65e 100644
--- a/src/mainboard/google/veyron/reset.c
+++ b/src/mainboard/google/veyron/reset.c
@@ -19,8 +19,7 @@
 
 #include "board.h"
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	gpio_output(GPIO_RESET, 1);
-	while (1);
 }
diff --git a/src/mainboard/google/veyron_mickey/reset.c b/src/mainboard/google/veyron_mickey/reset.c
index 0d11e76f70..a937aff65e 100644
--- a/src/mainboard/google/veyron_mickey/reset.c
+++ b/src/mainboard/google/veyron_mickey/reset.c
@@ -19,8 +19,7 @@
 
 #include "board.h"
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	gpio_output(GPIO_RESET, 1);
-	while (1);
 }
diff --git a/src/mainboard/google/veyron_rialto/reset.c b/src/mainboard/google/veyron_rialto/reset.c
index cf3a6d8a2f..a937aff65e 100644
--- a/src/mainboard/google/veyron_rialto/reset.c
+++ b/src/mainboard/google/veyron_rialto/reset.c
@@ -19,9 +19,7 @@
 
 #include "board.h"
 
-void hard_reset(void)
+void do_hard_reset(void)
 {
 	gpio_output(GPIO_RESET, 1);
-	while (1)
-		;
 }