Subject: Re: fsl_upm compile failure.

From: Anton Vorontsov <[email-masked]>
Date: Thu, 9 Oct 2008 03:02:19 +0400

Hi,

On Wed, Oct 08, 2008 at 06:28:15PM -0400, Dave Jones wrote:
> Hi Anton, 
>  I tried reenabling CONFIG_MTD_NAND_FSL_UPM in the Fedora kernel
> today (currently on 2.6.27-rc9-git1), and got the error below.
> 
> ERROR: "fsl_lbc_lock" [drivers/mtd/nand/fsl_upm.ko] undefined!

Weird. It works for me with mpc836x_rdk_defconfig and
MTD_NAND_FSL_UPM=m...

Hm..

  CC      drivers/mtd/nand/fsl_upm.mod.o
  LD [M]  drivers/mtd/nand/fsl_upm.ko

Can you send me the .config file you use?

> It seems that this isn't exported to modules.
> diff below fixes this.  (Not tested yet, the Fedora ppc
>  builders are a little slow).
> 
> 	Dave
> 
> --- 
> 
> CONFIG_MTD_NAND_FSL_UPM can be built modular, but needs to
> use fsl_lbc_lock, which isn't currently exported.
> 
> Signed-off-by: Dave Jones <[email-masked]>
> 
> diff --git a/arch/powerpc/sysdev/fsl_lbc.c b/arch/powerpc/sysdev/fsl_lbc.c
> index 422c8fa..1c6c522 100644
> --- a/arch/powerpc/sysdev/fsl_lbc.c
> +++ b/arch/powerpc/sysdev/fsl_lbc.c
> @@ -16,6 +16,7 @@
>  #include <asm/fsl_lbc.h>
>
>  spinlock_t fsl_lbc_lock = __SPIN_LOCK_UNLOCKED(fsl_lbc_lock);
> +EXPORT_SYMBOL(fsl_lbc_lock);
>
>  struct fsl_lbc_regs __iomem *fsl_lbc_regs;
>  EXPORT_SYMBOL(fsl_lbc_regs);

But the patch looks obviously correct. Much thanks for catching this.

Though better option would be to uninline the fsl_upm_run_pattern()..
it is quite big anyway... Something like this:

diff --git a/arch/powerpc/include/asm/fsl_lbc.h b/arch/powerpc/include/asm/fsl_lbc.h
index 303f548..af2b535 100644
--- a/arch/powerpc/include/asm/fsl_lbc.h
+++ b/arch/powerpc/include/asm/fsl_lbc.h
@@ -24,7 +24,6 @@
 #define __ASM_FSL_LBC_H
 
 #include <linux/types.h>
-#include <linux/spinlock.h>
 #include <asm/io.h>
 
 struct fsl_lbc_bank {
@@ -228,7 +227,6 @@ struct fsl_lbc_regs {
 };
 
 extern struct fsl_lbc_regs __iomem *fsl_lbc_regs;
-extern spinlock_t fsl_lbc_lock;
 
 /*
  * FSL UPM routines
@@ -268,44 +266,7 @@ static inline void fsl_upm_end_pattern(struct fsl_upm *upm)
 		cpu_relax();
 }
 
-/**
- * fsl_upm_run_pattern - actually run an UPM pattern
- * @upm:	pointer to the fsl_upm structure obtained via fsl_upm_find
- * @io_base:	remapped pointer to where memory access should happen
- * @mar:	MAR register content during pattern execution
- *
- * This function triggers dummy write to the memory specified by the io_base,
- * thus UPM pattern actually executed. Note that mar usage depends on the
- * pre-programmed AMX bits in the UPM RAM.
- */
-static inline int fsl_upm_run_pattern(struct fsl_upm *upm,
-				      void __iomem *io_base, u32 mar)
-{
-	int ret = 0;
-	unsigned long flags;
-
-	spin_lock_irqsave(&fsl_lbc_lock, flags);
-
-	out_be32(&fsl_lbc_regs->mar, mar << (32 - upm->width));
-
-	switch (upm->width) {
-	case 8:
-		out_8(io_base, 0x0);
-		break;
-	case 16:
-		out_be16(io_base, 0x0);
-		break;
-	case 32:
-		out_be32(io_base, 0x0);
-		break;
-	default:
-		ret = -EINVAL;
-		break;
-	}
-
-	spin_unlock_irqrestore(&fsl_lbc_lock, flags);
-
-	return ret;
-}
+extern int fsl_upm_run_pattern(struct fsl_upm *upm, void __iomem *io_base,
+			       u32 mar);
 
 #endif /* __ASM_FSL_LBC_H */
diff --git a/arch/powerpc/sysdev/fsl_lbc.c b/arch/powerpc/sysdev/fsl_lbc.c
index 422c8fa..d81297c 100644
--- a/arch/powerpc/sysdev/fsl_lbc.c
+++ b/arch/powerpc/sysdev/fsl_lbc.c
@@ -13,6 +13,7 @@
 
 #include <linux/kernel.h>
 #include <linux/of.h>
+#include <linux/spinlock.h>
 #include <asm/fsl_lbc.h>
 
 spinlock_t fsl_lbc_lock = __SPIN_LOCK_UNLOCKED(fsl_lbc_lock);
@@ -127,3 +128,43 @@ int fsl_upm_find(phys_addr_t addr_base, struct fsl_upm *upm)
 	return 0;
 }
 EXPORT_SYMBOL(fsl_upm_find);
+
+/**
+ * fsl_upm_run_pattern - actually run an UPM pattern
+ * @upm:	pointer to the fsl_upm structure obtained via fsl_upm_find
+ * @io_base:	remapped pointer to where memory access should happen
+ * @mar:	MAR register content during pattern execution
+ *
+ * This function triggers dummy write to the memory specified by the io_base,
+ * thus UPM pattern actually executed. Note that mar usage depends on the
+ * pre-programmed AMX bits in the UPM RAM.
+ */
+int fsl_upm_run_pattern(struct fsl_upm *upm, void __iomem *io_base, u32 mar)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&fsl_lbc_lock, flags);
+
+	out_be32(&fsl_lbc_regs->mar, mar << (32 - upm->width));
+
+	switch (upm->width) {
+	case 8:
+		out_8(io_base, 0x0);
+		break;
+	case 16:
+		out_be16(io_base, 0x0);
+		break;
+	case 32:
+		out_be32(io_base, 0x0);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	spin_unlock_irqrestore(&fsl_lbc_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(fsl_upm_run_pattern);

(This also adds missing linux/spinlock.h include to the fsl_lbc.c)

Anyhow, whatever approach you chose, feel free to add my:

Acked-by: Anton Vorontsov <[email-masked]>

Then please resend the patch with added
Cc: Kumar Gala <[email-masked]>, [email-masked]

^^ Kumar would apply the patch to his powerpc.git tree, powerpc-next branch.

-- 
Anton Vorontsov
email: [email-masked]
irc://irc.freenode.net/bd2