[PATCH 4/4] [DRIVERS] add a register dumper for debugging

Add a dumper to examine the changes of the registers before and after
calling the Toshiba SMM.

Signed-off-by: Henrik Kretzschmar <[email protected]>
---
 drivers/char/toshiba.c |   20 ++++++++++++++++++++
 1 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/drivers/char/toshiba.c b/drivers/char/toshiba.c
index 111baba..626d281 100644
--- a/drivers/char/toshiba.c
+++ b/drivers/char/toshiba.c
@@ -75,6 +75,20 @@
 #define DRV_NAME "toshiba"
 #define TOSH_MINOR_DEV 181
 
+#if TOSH_DEBUG == 1
+static void pr_smmregs(SMMRegisters *regs)
+{
+	printk(KERN_DEBUG DRV_NAME " EAX: 0x%08x EBX: 0x%08x ECX: 0x%08x\n",
+	       regs->eax, regs->ebx, regs->ecx);
+	printk(KERN_DEBUG DRV_NAME " EDX: 0x%08x ESI: 0x%08x EDI: 0x%08x\n",
+	       regs->edx, regs->esi, regs->edi);
+}
+#else
+static inline void pr_smmregs(SMMRegisters *regs)
+{
+}
+#endif
+
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Jonathan Buzzard <[email protected]>");
 MODULE_DESCRIPTION("Toshiba laptop SMM driver");
@@ -220,6 +234,9 @@ int tosh_smm(SMMRegisters *regs)
 {
 	int eax;
 
+	printk(KERN_DEBUG DRV_NAME " %s start\n", __func__);
+	pr_smmregs(regs);
+
 	asm ("# load the values into the registers\n\t" \
 		"pushl %%eax\n\t" \
 		"movl 0(%%eax),%%edx\n\t" \
@@ -249,6 +266,9 @@ int tosh_smm(SMMRegisters *regs)
 		: "a" (regs)
 		: "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 
+	pr_smmregs(regs);
+	printk(KERN_DEBUG DRV_NAME " %s done\n", __func__);
+
 	return eax;
 }
 EXPORT_SYMBOL(tosh_smm);
-- 
1.6.5