sparc64: Add generic interface for registering a dimm printing handler.

The way to do this varies by platform type and the exact memory
controller the cpu uses.

For Spitfire cpus we currently just use prom_getunumber() and hope
that works.

For Cheetah cpus we have a memory controller driver that can
compute this information.
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/include/asm/memctrl.h

+#ifndef _SPARC_MEMCTRL_H
+#define _SPARC_MEMCTRL_H
+
+typedef int (*dimm_printer_t)(int synd_code, unsigned long paddr, char *buf, int buflen);
+
+int register_dimm_printer(dimm_printer_t func);
+void unregister_dimm_printer(dimm_printer_t func);
+
+#endif /* _SPARC_MEMCTRL_H */

arch/sparc64/kernel/chmc.c

@@ -22,6 +22,7 @@
 #include <asm/prom.h>
 #include <asm/head.h>
 #include <asm/io.h>
+#include <asm/memctrl.h>
 
 #define DRV_MODULE_NAME		"chmc"
 #define PFX DRV_MODULE_NAME	": "
@@ -158,9 +159,9 @@ static struct chmc_bank_info *chmc_find_bank(unsigned long phys_addr)
 /* This is the main purpose of this driver. */
 #define SYNDROME_MIN	-1
 #define SYNDROME_MAX	144
-int chmc_getunumber(int syndrome_code,
-		    unsigned long phys_addr,
-		    char *buf, int buflen)
+static int chmc_print_dimm(int syndrome_code,
+			   unsigned long phys_addr,
+			   char *buf, int buflen)
 {
 	struct chmc_bank_info *bp;
 	struct chmc_obp_mem_layout *prop;
@@ -466,16 +467,26 @@ static inline bool chmc_platform(void)
 
 static int __init chmc_init(void)
 {
+	int ret;
+
 	if (!chmc_platform())
 		return -ENODEV;
 
-	return of_register_driver(&chmc_driver, &of_bus_type);
+	ret = register_dimm_printer(chmc_print_dimm);
+	if (!ret) {
+		ret = of_register_driver(&chmc_driver, &of_bus_type);
+		if (ret)
+			unregister_dimm_printer(chmc_print_dimm);
+	}
+	return ret;
 }
 
 static void __exit chmc_cleanup(void)
 {
-	if (chmc_platform())
+	if (chmc_platform()) {
+		unregister_dimm_printer(chmc_print_dimm);
 		of_unregister_driver(&chmc_driver);
+	}
 }
 
 module_init(chmc_init);

arch/sparc64/kernel/traps.c

@@ -37,6 +37,7 @@
 #include <asm/timer.h>
 #include <asm/head.h>
 #include <asm/prom.h>
+#include <asm/memctrl.h>
 
 #include "entry.h"
 #include "kstack.h"
@@ -128,6 +129,55 @@ void do_BUG(const char *file, int line)
 }
 #endif
 
+static DEFINE_SPINLOCK(dimm_handler_lock);
+static dimm_printer_t dimm_handler;
+
+static int sprintf_dimm(int synd_code, unsigned long paddr, char *buf, int buflen)
+{
+	unsigned long flags;
+	int ret = -ENODEV;
+
+	spin_lock_irqsave(&dimm_handler_lock, flags);
+	if (dimm_handler) {
+		ret = dimm_handler(synd_code, paddr, buf, buflen);
+	} else if (tlb_type == spitfire) {
+		if (prom_getunumber(synd_code, paddr, buf, buflen) == -1)
+			ret = -EINVAL;
+		else
+			ret = 0;
+	} else
+		ret = -ENODEV;
+	spin_unlock_irqrestore(&dimm_handler_lock, flags);
+
+	return ret;
+}
+
+int register_dimm_printer(dimm_printer_t func)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&dimm_handler_lock, flags);
+	if (!dimm_handler)
+		dimm_handler = func;
+	else
+		ret = -EEXIST;
+	spin_unlock_irqrestore(&dimm_handler_lock, flags);
+
+	return ret;
+}
+
+void unregister_dimm_printer(dimm_printer_t func)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dimm_handler_lock, flags);
+	if (dimm_handler == func)
+		dimm_handler = NULL;
+	spin_unlock_irqrestore(&dimm_handler_lock, flags);
+}
+
+
 void spitfire_insn_access_exception(struct pt_regs *regs, unsigned long sfsr, unsigned long sfar)
 {
 	siginfo_t info;
@@ -375,8 +425,7 @@ static void spitfire_log_udb_syndrome(unsigned long afar, unsigned long udbh, un
 
 	if (udbl & bit) {
 		scode = ecc_syndrome_table[udbl & 0xff];
-		if (prom_getunumber(scode, afar,
-				    memmod_str, sizeof(memmod_str)) == -1)
+		if (sprintf_dimm(scode, afar, memmod_str, sizeof(memmod_str)) < 0)
 			p = syndrome_unknown;
 		else
 			p = memmod_str;
@@ -387,8 +436,7 @@ static void spitfire_log_udb_syndrome(unsigned long afar, unsigned long udbh, un
 
 	if (udbh & bit) {
 		scode = ecc_syndrome_table[udbh & 0xff];
-		if (prom_getunumber(scode, afar,
-				    memmod_str, sizeof(memmod_str)) == -1)
+		if (sprintf_dimm(scode, afar, memmod_str, sizeof(memmod_str)) < 0)
 			p = syndrome_unknown;
 		else
 			p = memmod_str;
@@ -1061,8 +1109,6 @@ static const char *cheetah_get_string(unsigned long bit)
 	return "???";
 }
 
-extern int chmc_getunumber(int, unsigned long, char *, int);
-
 static void cheetah_log_errors(struct pt_regs *regs, struct cheetah_err_info *info,
 			       unsigned long afsr, unsigned long afar, int recoverable)
 {
@@ -1104,7 +1150,7 @@ static void cheetah_log_errors(struct pt_regs *regs, struct cheetah_err_info *in
 
 		syndrome = (afsr & CHAFSR_E_SYNDROME) >> CHAFSR_E_SYNDROME_SHIFT;
 		syndrome = cheetah_ecc_syntab[syndrome];
-		ret = chmc_getunumber(syndrome, afar, unum, sizeof(unum));
+		ret = sprintf_dimm(syndrome, afar, unum, sizeof(unum));
 		if (ret != -1)
 			printk("%s" "ERROR(%d): AFAR E-syndrome [%s]\n",
 			       (recoverable ? KERN_WARNING : KERN_CRIT),
@@ -1115,7 +1161,7 @@ static void cheetah_log_errors(struct pt_regs *regs, struct cheetah_err_info *in
 
 		syndrome = (afsr & CHAFSR_M_SYNDROME) >> CHAFSR_M_SYNDROME_SHIFT;
 		syndrome = cheetah_mtag_syntab[syndrome];
-		ret = chmc_getunumber(syndrome, afar, unum, sizeof(unum));
+		ret = sprintf_dimm(syndrome, afar, unum, sizeof(unum));
 		if (ret != -1)
 			printk("%s" "ERROR(%d): AFAR M-syndrome [%s]\n",
 			       (recoverable ? KERN_WARNING : KERN_CRIT),