[U-Boot] [PATCH] IXP425: make cmd_go handle caches correctly Part 1/1

[U-Boot] [PATCH] IXP425: make cmd_go handle caches correctly Part 1/1

[Stefan Althoefer]

[PATCH] IXP425: make cmd_go handle caches correctly

This patch adds icache_invalidate() and dcache_flush() to
cpu/ixp/cpu.c.

Also it adds do_go_exec() which is called from do_go().
This private implementation performs cache handling
before jumping into the code.

Without this cache handling, you will jump into stale
code if you download a program several times.


The patch is against "latest" u-boot git-repository

Please (still) be patient if style of submission or patches are
offending.

Signed-off-by: Stefan Althoefer <stefan.althoefer@web.de>
----

diff -uprN u-boot-orig//cpu/ixp/cpu.c u-boot/cpu/ixp/cpu.c
--- u-boot-orig//cpu/ixp/cpu.c	2008-12-02 17:25:31.000000000 +0100
+++ u-boot/cpu/ixp/cpu.c	2008-12-03 11:35:37.000000000 +0100
@@ -171,6 +207,22 @@ int icache_status (void)
 	return (i & 0x1000);
 }
 
+void icache_invalidate (void)
+{
+        register u32 i;
+
+        /* FIXME: Required to check if icache is enabled before we do this? */
+        
+        /* invalidate I-cache (i is ignored)*/
+	i = 0;
+        asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
+
+        /* cpwait */
+        asm ("mrc  p15,0,%0,c2,c0,0;\
+            mov  %0,%0;\
+            sub  pc,pc,#4" : : "r" (i) );
+}
+
 /* we will never enable dcache, because we have to setup MMU first */
 void dcache_enable (void)
 {
@@ -187,6 +239,11 @@ int dcache_status (void)
 	return 0;					/* always off */
 }
 
+void dcache_flush (void)
+{
+	return;
+}
+
 /* FIXME */
 /*
 void pci_init(void)
@@ -195,6 +252,17 @@ void pci_init(void)
 }
 */
 
+/* With IXP (and ARM generally) we need to handle caches to avoid
+   stale data. */
+unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char *argv[])
+{ 
+	dcache_flush();
+	icache_invalidate();
+
+        return entry (argc, argv);
+}
+
+
 #ifdef CONFIG_BOOTCOUNT_LIMIT
 
 void bootcount_store (ulong a)

[U-Boot] [PATCH] IXP425: make cmd_go handle caches correctly Part 1/1

[Wolfgang Denk]

Dear Stefan Althoefer,

In message <49384710.DwdG58IaB1mKOO9U%stefan.althoefer@web.de> you wrote:
> [PATCH] IXP425: make cmd_go handle caches correctly
> 
> This patch adds icache_invalidate() and dcache_flush() to
> cpu/ixp/cpu.c.
> 
> Also it adds do_go_exec() which is called from do_go().
> This private implementation performs cache handling
> before jumping into the code.
> 
> Without this cache handling, you will jump into stale
> code if you download a program several times.

Coding style: please use TABs for indentation.

> The patch is against "latest" u-boot git-repository
> 
> Please (still) be patient if style of submission or patches are
> offending.

And move such comments below th e"---" line, please.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
The first thing we do is kill all the lawyers.
(Shakespeare. II Henry VI, Act IV, scene ii)

[U-Boot] [PATCH] IXP425: make cmd_go handle caches correctly Part 1/1

[Stefan Althoefer]

IXP425: make cmd_go handle caches correctly

This patch adds icache_invalidate() and dcache_flush() to
cpu/ixp/cpu.c.

Also it adds do_go_exec() which is called from do_go().
This private implementation performs cache handling
before jumping into the code.

Without this cache handling, you will jump into stale
code if you download a program several times.

Signed-off-by: Stefan Althoefer <stefan.althoefer@web.de>
---

>
> Coding style: please use TABs for indentation.
>

Sorry for the spaces.

BTW: In function calls: Is the space between function name
are opening bracket desired or not? Seems this is handled
very inconsistent.

-- Stefan

 cpu/ixp/cpu.c |   32 ++++++++++++++++++++++++++++++++
 1 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/cpu/ixp/cpu.c b/cpu/ixp/cpu.c
index 27872fb..9035d98 100644
--- a/cpu/ixp/cpu.c
+++ b/cpu/ixp/cpu.c
@@ -171,6 +171,22 @@ int icache_status (void)
 	return (i & 0x1000);
 }

+void icache_invalidate (void)
+{
+	register u32 i;
+
+	/* FIXME: Required to check if icache is enabled before we do this? */
+
+	/* invalidate I-cache (i is ignored)*/
+	i = 0;
+	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
+
+	/* cpwait */
+	asm ("mrc  p15,0,%0,c2,c0,0;\
+	    mov  %0,%0;\
+	    sub  pc,pc,#4" : : "r" (i) );
+}
+
 /* we will never enable dcache, because we have to setup MMU first */
 void dcache_enable (void)
 {
@@ -187,6 +203,11 @@ int dcache_status (void)
 	return 0;					/* always off */
 }

+void dcache_flush (void)
+{
+	return;
+}
+
 /* FIXME */
 /*
 void pci_init(void)
@@ -195,6 +216,17 @@ void pci_init(void)
 }
 */

+/* With IXP (and ARM generally) we need to handle caches to avoid
+   stale data. */
+unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char *argv[])
+{
+	dcache_flush ();
+	icache_invalidate ();
+
+	return entry (argc, argv);
+}
+
+
 #ifdef CONFIG_BOOTCOUNT_LIMIT

 void bootcount_store (ulong a)
-- 
1.5.6

[U-Boot] [PATCH] IXP425: make cmd_go handle caches correctly Part 1/1

[Jean-Christophe PLAGNIOL-VILLARD]

> 
> diff --git a/cpu/ixp/cpu.c b/cpu/ixp/cpu.c
> index 27872fb..9035d98 100644
> --- a/cpu/ixp/cpu.c
> +++ b/cpu/ixp/cpu.c
> @@ -171,6 +171,22 @@ int icache_status (void)
>  	return (i & 0x1000);
>  }
> 
> +void icache_invalidate (void)
> +{
> +	register u32 i;
why do you need it?
> +
> +	/* FIXME: Required to check if icache is enabled before we do this? */
> +
> +	/* invalidate I-cache (i is ignored)*/
> +	i = 0;
> +	asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
> +
> +	/* cpwait */
> +	asm ("mrc  p15,0,%0,c2,c0,0;\
> +	    mov  %0,%0;\
> +	    sub  pc,pc,#4" : : "r" (i) );
> +}
> +
>  /* we will never enable dcache, because we have to setup MMU first */
>  void dcache_enable (void)
>  {
> @@ -187,6 +203,11 @@ int dcache_status (void)
>  	return 0;					/* always off */
>  }
> 
> +void dcache_flush (void)
> +{
> +	return;
> +}
> +
>  /* FIXME */
>  /*
>  void pci_init(void)
> @@ -195,6 +216,17 @@ void pci_init(void)
>  }
>  */
> 
general arm function need to be in the lib_arm
> +/* With IXP (and ARM generally) we need to handle caches to avoid
> +   stale data. */
> +unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char *argv[])
> +{
> +	dcache_flush ();
> +	icache_invalidate ();
> +
> +	return entry (argc, argv);
> +}
> +
Best Regards,
J.