[U-Boot] [PATCH] [v2] fix print_size printing fractional gigabyte numbers on 32-bit platforms

[U-Boot] [PATCH] [v2] fix print_size printing fractional gigabyte numbers on 32-bit platforms

[Timur Tabi]

In print_size(), the math that calculates the fractional remainder of a number
used the same integer size as a physical address.  However, the "10 *" factor
of the algorithm means that a large number (e.g. 1.5GB) can overflow the
integer if we're running on a 32-bit system.  Therefore, we need to
disassociate this function from the size of a physical address.

Signed-off-by: Timur Tabi <timur@freescale.com>
---
 include/common.h              |    2 +-
 lib_generic/display_options.c |    6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/common.h b/include/common.h
index a133e34..4e77727 100644
--- a/include/common.h
+++ b/include/common.h
@@ -218,7 +218,7 @@ void	hang		(void) __attribute__ ((noreturn));
 /* */
 phys_size_t initdram (int);
 int	display_options (void);
-void	print_size (phys_size_t, const char *);
+void	print_size(unsigned long long, const char *);
 int	print_buffer (ulong addr, void* data, uint width, uint count, uint linelen);
 
 /* common/main.c */
diff --git a/lib_generic/display_options.c b/lib_generic/display_options.c
index 2dc2567..da17a62 100644
--- a/lib_generic/display_options.c
+++ b/lib_generic/display_options.c
@@ -43,10 +43,10 @@ int display_options (void)
  * xxx GB, or xxx.y GB as needed; allow for optional trailing string
  * (like "\n")
  */
-void print_size (phys_size_t size, const char *s)
+void print_size(unsigned long long size, const char *s)
 {
-	ulong m = 0, n;
-	phys_size_t d = 1 << 30;		/* 1 GB */
+	unsigned long m = 0, n;
+	unsigned long long d = 1 << 30; 	/* 1 GB */
 	char  c = 'G';
 
 	if (size < d) {			/* try MB */
-- 
1.6.5

[U-Boot] [PATCH] [v2] fix print_size printing fractional gigabyte numbers on 32-bit platforms

[Scott Wood]

Timur Tabi wrote:
> In print_size(), the math that calculates the fractional remainder of a number
> used the same integer size as a physical address.  However, the "10 *" factor
> of the algorithm means that a large number (e.g. 1.5GB) can overflow the
> integer if we're running on a 32-bit system.  Therefore, we need to
> disassociate this function from the size of a physical address.
> 
> Signed-off-by: Timur Tabi <timur@freescale.com>
> ---
>  include/common.h              |    2 +-
>  lib_generic/display_options.c |    6 +++---
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/include/common.h b/include/common.h
> index a133e34..4e77727 100644
> --- a/include/common.h
> +++ b/include/common.h
> @@ -218,7 +218,7 @@ void	hang		(void) __attribute__ ((noreturn));
>  /* */
>  phys_size_t initdram (int);
>  int	display_options (void);
> -void	print_size (phys_size_t, const char *);
> +void	print_size(unsigned long long, const char *);

As stated before, the overflow is an implementation detail.  There's no 
reason to change the interface unless there's a desire to support 
printing sizes larger than phys_size_t, which is a distinct issue from 
the bugfix.

-Scott

[U-Boot] [PATCH] [v2] fix print_size printing fractional gigabyte numbers on 32-bit platforms

[Timur Tabi]

Scott Wood wrote:
> As stated before, the overflow is an implementation detail.  There's no 
> reason to change the interface unless there's a desire to support 
> printing sizes larger than phys_size_t, which is a distinct issue from 
> the bugfix.

You are correct.  I'll post a new patch.  However, there's a lot of value in being able to print >4GB numbers on a 32-bit system, and it seems silly to make two patches.  I'll post a new patch, and Wolfgang can decide what he wants.

-- 
Timur Tabi
Linux kernel developer at Freescale