[PATCH v1] x86/PCI: Make pci=earlydump output neat

[PATCH v1] x86/PCI: Make pci=earlydump output neat

[Andy Shevchenko]

Currently the early dump of PCI configuration space looks quite unhelpful, e.g.

[    0.000000]   60:
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]  00
[    0.000000]

which makes really hard to get anything out of this. Convert the function to
use print_hex_dump() to make output neat.

In the result we will have

[    0.000000] 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

which is much, much better.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 arch/x86/pci/early.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
index f0114007e915..53a87692d687 100644
--- a/arch/x86/pci/early.c
+++ b/arch/x86/pci/early.c
@@ -59,24 +59,15 @@ int early_pci_allowed(void)
 
 void early_dump_pci_device(u8 bus, u8 slot, u8 func)
 {
+	u32 value[256 / 4];
 	int i;
-	int j;
-	u32 val;
 
-	printk(KERN_INFO "pci 0000:%02x:%02x.%d config space:",
-	       bus, slot, func);
+	pr_info("pci 0000:%02x:%02x.%d config space:\n", bus, slot, func);
 
-	for (i = 0; i < 256; i += 4) {
-		if (!(i & 0x0f))
-			printk("\n  %02x:",i);
+	for (i = 0; i < 256; i += 4)
+		value[i/4] = read_pci_config(bus, slot, func, i);
 
-		val = read_pci_config(bus, slot, func, i);
-		for (j = 0; j < 4; j++) {
-			printk(" %02x", val & 0xff);
-			val >>= 8;
-		}
-	}
-	printk("\n");
+	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1, value, 256, false);
 }
 
 void early_dump_pci_devices(void)
-- 
2.16.3

Re: [PATCH v1] x86/PCI: Make pci=earlydump output neat

[Mika Westerberg]

On Thu, Apr 05, 2018 at 03:11:59PM +0300, Andy Shevchenko wrote:
> Currently the early dump of PCI configuration space looks quite unhelpful, e.g.
> 
> [    0.000000]   60:
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]  00
> [    0.000000]
> 
> which makes really hard to get anything out of this. Convert the function to
> use print_hex_dump() to make output neat.
> 
> In the result we will have
> 
> [    0.000000] 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> 
> which is much, much better.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  arch/x86/pci/early.c | 19 +++++--------------
>  1 file changed, 5 insertions(+), 14 deletions(-)
> 
> diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
> index f0114007e915..53a87692d687 100644
> --- a/arch/x86/pci/early.c
> +++ b/arch/x86/pci/early.c
> @@ -59,24 +59,15 @@ int early_pci_allowed(void)
>  
>  void early_dump_pci_device(u8 bus, u8 slot, u8 func)
>  {
> +	u32 value[256 / 4];
>  	int i;
> -	int j;
> -	u32 val;
>  
> -	printk(KERN_INFO "pci 0000:%02x:%02x.%d config space:",
> -	       bus, slot, func);
> +	pr_info("pci 0000:%02x:%02x.%d config space:\n", bus, slot, func);
>  
> -	for (i = 0; i < 256; i += 4) {
> -		if (!(i & 0x0f))
> -			printk("\n  %02x:",i);
> +	for (i = 0; i < 256; i += 4)
> +		value[i/4] = read_pci_config(bus, slot, func, i);

Please be consistent with your use of whitespace: 256 / 4 vs. i/4.

Other than that looks good and certainly is an improvement,

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>