* [PATCH] x86/PCI: simplify pci_bios_{read,write}
@ 2015-12-07 13:42 Geliang Tang
2015-12-08 12:16 ` Thomas Gleixner
2015-12-09 16:50 ` Bjorn Helgaas
0 siblings, 2 replies; 3+ messages in thread
From: Geliang Tang @ 2015-12-07 13:42 UTC (permalink / raw)
To: Bjorn Helgaas, Thomas Gleixner, Ingo Molnar, H. Peter Anvin
Cc: Geliang Tang, x86, linux-pci, linux-kernel
There are some repetitive code in the switch/case statement in
pci_bios_read() and pci_bios_write(). I drop it to simplify the
code.
Signed-off-by: Geliang Tang <geliangtang@163.com>
---
arch/x86/pci/pcbios.c | 108 ++++++++++++++++++--------------------------------
1 file changed, 38 insertions(+), 70 deletions(-)
diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c
index 9b83b90..9770e55 100644
--- a/arch/x86/pci/pcbios.c
+++ b/arch/x86/pci/pcbios.c
@@ -180,6 +180,7 @@ static int pci_bios_read(unsigned int seg, unsigned int bus,
unsigned long result = 0;
unsigned long flags;
unsigned long bx = (bus << 8) | devfn;
+ u16 number = 0, mask = 0;
WARN_ON(seg);
if (!value || (bus > 255) || (devfn > 255) || (reg > 255))
@@ -189,53 +190,35 @@ static int pci_bios_read(unsigned int seg, unsigned int bus,
switch (len) {
case 1:
- __asm__("lcall *(%%esi); cld\n\t"
- "jc 1f\n\t"
- "xor %%ah, %%ah\n"
- "1:"
- : "=c" (*value),
- "=a" (result)
- : "1" (PCIBIOS_READ_CONFIG_BYTE),
- "b" (bx),
- "D" ((long)reg),
- "S" (&pci_indirect));
- /*
- * Zero-extend the result beyond 8 bits, do not trust the
- * BIOS having done it:
- */
- *value &= 0xff;
+ number = PCIBIOS_READ_CONFIG_BYTE;
+ mask = 0xff;
break;
case 2:
- __asm__("lcall *(%%esi); cld\n\t"
- "jc 1f\n\t"
- "xor %%ah, %%ah\n"
- "1:"
- : "=c" (*value),
- "=a" (result)
- : "1" (PCIBIOS_READ_CONFIG_WORD),
- "b" (bx),
- "D" ((long)reg),
- "S" (&pci_indirect));
- /*
- * Zero-extend the result beyond 16 bits, do not trust the
- * BIOS having done it:
- */
- *value &= 0xffff;
+ number = PCIBIOS_READ_CONFIG_WORD;
+ mask = 0xffff;
break;
case 4:
- __asm__("lcall *(%%esi); cld\n\t"
- "jc 1f\n\t"
- "xor %%ah, %%ah\n"
- "1:"
- : "=c" (*value),
- "=a" (result)
- : "1" (PCIBIOS_READ_CONFIG_DWORD),
- "b" (bx),
- "D" ((long)reg),
- "S" (&pci_indirect));
+ number = PCIBIOS_READ_CONFIG_DWORD;
break;
}
+ __asm__("lcall *(%%esi); cld\n\t"
+ "jc 1f\n\t"
+ "xor %%ah, %%ah\n"
+ "1:"
+ : "=c" (*value),
+ "=a" (result)
+ : "1" (number),
+ "b" (bx),
+ "D" ((long)reg),
+ "S" (&pci_indirect));
+ /*
+ * Zero-extend the result beyond 8 or 16 bits, do not trust the
+ * BIOS having done it:
+ */
+ if (mask)
+ *value &= mask;
+
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
return (int)((result & 0xff00) >> 8);
@@ -247,6 +230,7 @@ static int pci_bios_write(unsigned int seg, unsigned int bus,
unsigned long result = 0;
unsigned long flags;
unsigned long bx = (bus << 8) | devfn;
+ u16 number = 0;
WARN_ON(seg);
if ((bus > 255) || (devfn > 255) || (reg > 255))
@@ -256,43 +240,27 @@ static int pci_bios_write(unsigned int seg, unsigned int bus,
switch (len) {
case 1:
- __asm__("lcall *(%%esi); cld\n\t"
- "jc 1f\n\t"
- "xor %%ah, %%ah\n"
- "1:"
- : "=a" (result)
- : "0" (PCIBIOS_WRITE_CONFIG_BYTE),
- "c" (value),
- "b" (bx),
- "D" ((long)reg),
- "S" (&pci_indirect));
+ number = PCIBIOS_WRITE_CONFIG_BYTE;
break;
case 2:
- __asm__("lcall *(%%esi); cld\n\t"
- "jc 1f\n\t"
- "xor %%ah, %%ah\n"
- "1:"
- : "=a" (result)
- : "0" (PCIBIOS_WRITE_CONFIG_WORD),
- "c" (value),
- "b" (bx),
- "D" ((long)reg),
- "S" (&pci_indirect));
+ number = PCIBIOS_WRITE_CONFIG_WORD;
break;
case 4:
- __asm__("lcall *(%%esi); cld\n\t"
- "jc 1f\n\t"
- "xor %%ah, %%ah\n"
- "1:"
- : "=a" (result)
- : "0" (PCIBIOS_WRITE_CONFIG_DWORD),
- "c" (value),
- "b" (bx),
- "D" ((long)reg),
- "S" (&pci_indirect));
+ number = PCIBIOS_WRITE_CONFIG_DWORD;
break;
}
+ __asm__("lcall *(%%esi); cld\n\t"
+ "jc 1f\n\t"
+ "xor %%ah, %%ah\n"
+ "1:"
+ : "=a" (result)
+ : "0" (number),
+ "c" (value),
+ "b" (bx),
+ "D" ((long)reg),
+ "S" (&pci_indirect));
+
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
return (int)((result & 0xff00) >> 8);
--
2.5.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] x86/PCI: simplify pci_bios_{read,write}
2015-12-07 13:42 [PATCH] x86/PCI: simplify pci_bios_{read,write} Geliang Tang
@ 2015-12-08 12:16 ` Thomas Gleixner
2015-12-09 16:50 ` Bjorn Helgaas
1 sibling, 0 replies; 3+ messages in thread
From: Thomas Gleixner @ 2015-12-08 12:16 UTC (permalink / raw)
To: Geliang Tang
Cc: Bjorn Helgaas, Ingo Molnar, H. Peter Anvin, x86, linux-pci, linux-kernel
On Mon, 7 Dec 2015, Geliang Tang wrote:
> There are some repetitive code in the switch/case statement in
> pci_bios_read() and pci_bios_write(). I drop it to simplify the
> code.
>
> Signed-off-by: Geliang Tang <geliangtang@163.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] x86/PCI: simplify pci_bios_{read,write}
2015-12-07 13:42 [PATCH] x86/PCI: simplify pci_bios_{read,write} Geliang Tang
2015-12-08 12:16 ` Thomas Gleixner
@ 2015-12-09 16:50 ` Bjorn Helgaas
1 sibling, 0 replies; 3+ messages in thread
From: Bjorn Helgaas @ 2015-12-09 16:50 UTC (permalink / raw)
To: Geliang Tang
Cc: Bjorn Helgaas, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86,
linux-pci, linux-kernel
On Mon, Dec 07, 2015 at 10:24:24PM +0800, Geliang Tang wrote:
> There are some repetitive code in the switch/case statement in
> pci_bios_read() and pci_bios_write(). I drop it to simplify the
> code.
>
> Signed-off-by: Geliang Tang <geliangtang@163.com>
Applied to pci/misc for v4.5 with Thomas' Reviewed-by, thanks!
> ---
> arch/x86/pci/pcbios.c | 108 ++++++++++++++++++--------------------------------
> 1 file changed, 38 insertions(+), 70 deletions(-)
>
> diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c
> index 9b83b90..9770e55 100644
> --- a/arch/x86/pci/pcbios.c
> +++ b/arch/x86/pci/pcbios.c
> @@ -180,6 +180,7 @@ static int pci_bios_read(unsigned int seg, unsigned int bus,
> unsigned long result = 0;
> unsigned long flags;
> unsigned long bx = (bus << 8) | devfn;
> + u16 number = 0, mask = 0;
>
> WARN_ON(seg);
> if (!value || (bus > 255) || (devfn > 255) || (reg > 255))
> @@ -189,53 +190,35 @@ static int pci_bios_read(unsigned int seg, unsigned int bus,
>
> switch (len) {
> case 1:
> - __asm__("lcall *(%%esi); cld\n\t"
> - "jc 1f\n\t"
> - "xor %%ah, %%ah\n"
> - "1:"
> - : "=c" (*value),
> - "=a" (result)
> - : "1" (PCIBIOS_READ_CONFIG_BYTE),
> - "b" (bx),
> - "D" ((long)reg),
> - "S" (&pci_indirect));
> - /*
> - * Zero-extend the result beyond 8 bits, do not trust the
> - * BIOS having done it:
> - */
> - *value &= 0xff;
> + number = PCIBIOS_READ_CONFIG_BYTE;
> + mask = 0xff;
> break;
> case 2:
> - __asm__("lcall *(%%esi); cld\n\t"
> - "jc 1f\n\t"
> - "xor %%ah, %%ah\n"
> - "1:"
> - : "=c" (*value),
> - "=a" (result)
> - : "1" (PCIBIOS_READ_CONFIG_WORD),
> - "b" (bx),
> - "D" ((long)reg),
> - "S" (&pci_indirect));
> - /*
> - * Zero-extend the result beyond 16 bits, do not trust the
> - * BIOS having done it:
> - */
> - *value &= 0xffff;
> + number = PCIBIOS_READ_CONFIG_WORD;
> + mask = 0xffff;
> break;
> case 4:
> - __asm__("lcall *(%%esi); cld\n\t"
> - "jc 1f\n\t"
> - "xor %%ah, %%ah\n"
> - "1:"
> - : "=c" (*value),
> - "=a" (result)
> - : "1" (PCIBIOS_READ_CONFIG_DWORD),
> - "b" (bx),
> - "D" ((long)reg),
> - "S" (&pci_indirect));
> + number = PCIBIOS_READ_CONFIG_DWORD;
> break;
> }
>
> + __asm__("lcall *(%%esi); cld\n\t"
> + "jc 1f\n\t"
> + "xor %%ah, %%ah\n"
> + "1:"
> + : "=c" (*value),
> + "=a" (result)
> + : "1" (number),
> + "b" (bx),
> + "D" ((long)reg),
> + "S" (&pci_indirect));
> + /*
> + * Zero-extend the result beyond 8 or 16 bits, do not trust the
> + * BIOS having done it:
> + */
> + if (mask)
> + *value &= mask;
> +
> raw_spin_unlock_irqrestore(&pci_config_lock, flags);
>
> return (int)((result & 0xff00) >> 8);
> @@ -247,6 +230,7 @@ static int pci_bios_write(unsigned int seg, unsigned int bus,
> unsigned long result = 0;
> unsigned long flags;
> unsigned long bx = (bus << 8) | devfn;
> + u16 number = 0;
>
> WARN_ON(seg);
> if ((bus > 255) || (devfn > 255) || (reg > 255))
> @@ -256,43 +240,27 @@ static int pci_bios_write(unsigned int seg, unsigned int bus,
>
> switch (len) {
> case 1:
> - __asm__("lcall *(%%esi); cld\n\t"
> - "jc 1f\n\t"
> - "xor %%ah, %%ah\n"
> - "1:"
> - : "=a" (result)
> - : "0" (PCIBIOS_WRITE_CONFIG_BYTE),
> - "c" (value),
> - "b" (bx),
> - "D" ((long)reg),
> - "S" (&pci_indirect));
> + number = PCIBIOS_WRITE_CONFIG_BYTE;
> break;
> case 2:
> - __asm__("lcall *(%%esi); cld\n\t"
> - "jc 1f\n\t"
> - "xor %%ah, %%ah\n"
> - "1:"
> - : "=a" (result)
> - : "0" (PCIBIOS_WRITE_CONFIG_WORD),
> - "c" (value),
> - "b" (bx),
> - "D" ((long)reg),
> - "S" (&pci_indirect));
> + number = PCIBIOS_WRITE_CONFIG_WORD;
> break;
> case 4:
> - __asm__("lcall *(%%esi); cld\n\t"
> - "jc 1f\n\t"
> - "xor %%ah, %%ah\n"
> - "1:"
> - : "=a" (result)
> - : "0" (PCIBIOS_WRITE_CONFIG_DWORD),
> - "c" (value),
> - "b" (bx),
> - "D" ((long)reg),
> - "S" (&pci_indirect));
> + number = PCIBIOS_WRITE_CONFIG_DWORD;
> break;
> }
>
> + __asm__("lcall *(%%esi); cld\n\t"
> + "jc 1f\n\t"
> + "xor %%ah, %%ah\n"
> + "1:"
> + : "=a" (result)
> + : "0" (number),
> + "c" (value),
> + "b" (bx),
> + "D" ((long)reg),
> + "S" (&pci_indirect));
> +
> raw_spin_unlock_irqrestore(&pci_config_lock, flags);
>
> return (int)((result & 0xff00) >> 8);
> --
> 2.5.0
>
>
> --
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2015-12-08 12:16 ` Thomas Gleixner
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