thr3ads.net - Xen devel - [PATCH 6/8] ns16550: PCI initialization adjustments [Sep 2012]

If this information is useful, please help other people find it:
Share via:

Jan Beulich

2012-Sep-11 10:19 UTC

[PATCH 6/8] ns16550: PCI initialization adjustments

Besides single-port serial cards, also accept multi-port ones and such
providing mixed functionality (e.g. also having a parallel port).

Reading PCI_INTERRUPT_PIN before ACPI gets enabled generally produces
an incorrect IRQ (below 16, whereas after enabling ACPI it frequently
would end up at a higher one), so this is useful (almost) only when a
system already boots in ACPI mode.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/drivers/char/ns16550.c
+++ b/xen/drivers/char/ns16550.c
@@ -468,7 +468,6 @@ static int __init check_existence(struct
 static int
 pci_uart_config (struct ns16550 *uart, int skip_amt, int bar_idx)
 {
-    uint16_t class;
     uint32_t bar, len;
     int b, d, f;
 
@@ -479,9 +478,15 @@ pci_uart_config (struct ns16550 *uart, i
         {
             for ( f = 0; f < 0x8; f++ )
             {
-                class = pci_conf_read16(0, b, d, f, PCI_CLASS_DEVICE);
-                if ( class != 0x700 )
+                switch ( pci_conf_read16(0, b, d, f, PCI_CLASS_DEVICE) )
+                {
+                case 0x0700: /* single port serial */
+                case 0x0702: /* multi port serial */
+                case 0x0780: /* other (e.g serial+parallel) */
+                    break;
+                default:
                     continue;
+                }
 
                 bar = pci_conf_read32(0, b, d, f,
                                       PCI_BASE_ADDRESS_0 + bar_idx*4);
@@ -504,7 +509,9 @@ pci_uart_config (struct ns16550 *uart, i
                 uart->bar = bar;
                 uart->bar_idx = bar_idx;
                 uart->io_base = bar & ~PCI_BASE_ADDRESS_SPACE_IO;
-                uart->irq = 0;
+                uart->irq = pci_conf_read8(0, b, d, f, PCI_INTERRUPT_PIN) ?
+                    pci_conf_read8(0, b, d, f, PCI_INTERRUPT_LINE) : 0;
+printk("COM%d: BAR=%04x IRQ=%d\n", bar_idx + 1, bar,
uart->irq);//temp
 
                 return 0;
             }

Konrad Rzeszutek Wilk

2012-Sep-11 18:14 UTC

head link

Re: [PATCH 6/8] ns16550: PCI initialization adjustments

On Tue, Sep 11, 2012 at 11:19:32AM +0100, Jan Beulich
wrote:> Besides single-port serial cards, also accept multi-port ones and such
> providing mixed functionality (e.g. also having a parallel port).
> 
> Reading PCI_INTERRUPT_PIN before ACPI gets enabled generally produces
> an incorrect IRQ (below 16, whereas after enabling ACPI it frequently
> would end up at a higher one), so this is useful (almost) only when a
> system already boots in ACPI mode.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> --- a/xen/drivers/char/ns16550.c
> +++ b/xen/drivers/char/ns16550.c
> @@ -468,7 +468,6 @@ static int __init check_existence(struct
>  static int
>  pci_uart_config (struct ns16550 *uart, int skip_amt, int bar_idx)
>  {
> -    uint16_t class;
>      uint32_t bar, len;
>      int b, d, f;
>  
> @@ -479,9 +478,15 @@ pci_uart_config (struct ns16550 *uart, i
>          {
>              for ( f = 0; f < 0x8; f++ )
>              {
> -                class = pci_conf_read16(0, b, d, f, PCI_CLASS_DEVICE);
> -                if ( class != 0x700 )
> +                switch ( pci_conf_read16(0, b, d, f, PCI_CLASS_DEVICE) )
> +                {
> +                case 0x0700: /* single port serial */
> +                case 0x0702: /* multi port serial */
> +                case 0x0780: /* other (e.g serial+parallel) */
> +                    break;
> +                default:
>                      continue;
> +                }
>  
>                  bar = pci_conf_read32(0, b, d, f,
>                                        PCI_BASE_ADDRESS_0 + bar_idx*4);
> @@ -504,7 +509,9 @@ pci_uart_config (struct ns16550 *uart, i
>                  uart->bar = bar;
>                  uart->bar_idx = bar_idx;
>                  uart->io_base = bar & ~PCI_BASE_ADDRESS_SPACE_IO;
> -                uart->irq = 0;
> +                uart->irq = pci_conf_read8(0, b, d, f,
PCI_INTERRUPT_PIN) ?
> +                    pci_conf_read8(0, b, d, f, PCI_INTERRUPT_LINE) : 0;
> +printk("COM%d: BAR=%04x IRQ=%d\n", bar_idx + 1, bar,
uart->irq);//temp
printk ?
>  
>                  return 0;
>              }
> 
> 
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
>

Jan Beulich

2012-Sep-12 07:39 UTC

head link

Re: [PATCH 6/8] ns16550: PCI initialization adjustments

>>> On 11.09.12 at 20:14, Konrad Rzeszutek Wilk
<konrad@kernel.org> wrote:
> On Tue, Sep 11, 2012 at 11:19:32AM +0100, Jan Beulich wrote:
>> Besides single-port serial cards, also accept multi-port ones and such
>> providing mixed functionality (e.g. also having a parallel port).
>> 
>> Reading PCI_INTERRUPT_PIN before ACPI gets enabled generally produces
>> an incorrect IRQ (below 16, whereas after enabling ACPI it frequently
>> would end up at a higher one), so this is useful (almost) only when a
>> system already boots in ACPI mode.
>> 
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> 
>> --- a/xen/drivers/char/ns16550.c
>> +++ b/xen/drivers/char/ns16550.c
>> @@ -468,7 +468,6 @@ static int __init check_existence(struct
>>  static int
>>  pci_uart_config (struct ns16550 *uart, int skip_amt, int bar_idx)
>>  {
>> -    uint16_t class;
>>      uint32_t bar, len;
>>      int b, d, f;
>>  
>> @@ -479,9 +478,15 @@ pci_uart_config (struct ns16550 *uart, i
>>          {
>>              for ( f = 0; f < 0x8; f++ )
>>              {
>> -                class = pci_conf_read16(0, b, d, f, PCI_CLASS_DEVICE);
>> -                if ( class != 0x700 )
>> +                switch ( pci_conf_read16(0, b, d, f, PCI_CLASS_DEVICE)
)
>> +                {
>> +                case 0x0700: /* single port serial */
>> +                case 0x0702: /* multi port serial */
>> +                case 0x0780: /* other (e.g serial+parallel) */
>> +                    break;
>> +                default:
>>                      continue;
>> +                }
>>  
>>                  bar = pci_conf_read32(0, b, d, f,
>>                                        PCI_BASE_ADDRESS_0 + bar_idx*4);
>> @@ -504,7 +509,9 @@ pci_uart_config (struct ns16550 *uart, i
>>                  uart->bar = bar;
>>                  uart->bar_idx = bar_idx;
>>                  uart->io_base = bar &
~PCI_BASE_ADDRESS_SPACE_IO;
>> -                uart->irq = 0;
>> +                uart->irq = pci_conf_read8(0, b, d, f,
PCI_INTERRUPT_PIN) ?
>> +                    pci_conf_read8(0, b, d, f, PCI_INTERRUPT_LINE) :
0;
>> +printk("COM%d: BAR=%04x IRQ=%d\n", bar_idx + 1, bar,
uart->irq);//temp
> 
> printk ?
I had spotted this before committing, and removed it in time.

Thanks for noticing anyway,
Jan

Apparently Analagous Threads

Search for more maybe matching threads

Xen devel - Sep 2012 - [PATCH 6/8] ns16550: PCI initialization adjustments

[PATCH 6/8] ns16550: PCI initialization adjustments

Re: [PATCH 6/8] ns16550: PCI initialization adjustments

Re: [PATCH 6/8] ns16550: PCI initialization adjustments

Apparently Analagous Threads