Commit 6f3d5d3c authored by Michael Ellerman's avatar Michael Ellerman Committed by Paul Mackerras
Browse files

[POWERPC] Add a helper for calculating RTAS "config_addr" parameters 



Several RTAS calls take a "config_addr" parameter, which is a particular
way of specifying a PCI busno, devfn and register number into a 32-bit word.
Currently these are open-coded, and I'll be adding another soon, replace
them with a helper that encapsulates the logic. Be more strict about masking
the busno too, just in case.

Booted on P5 LPAR.

Signed-off-by: default avatarMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent a0a428e3

arch/powerpc/kernel/rtas_pci.c

+2 −4
Original line number Diff line number Diff line
@@ -81,8 +81,7 @@ int rtas_read_config(struct pci_dn *pdn, int where, int size, u32 *val) 
	if (!config_access_valid(pdn, where))

		return PCIBIOS_BAD_REGISTER_NUMBER;



	addr = ((where & 0xf00) << 20) | (pdn->busno << 16) |

		(pdn->devfn << 8) | (where & 0xff);

	addr = rtas_config_addr(pdn->busno, pdn->devfn, where);

	buid = pdn->phb->buid;

	if (buid) {

		ret = rtas_call(ibm_read_pci_config, 4, 2, &returnval,
@@ -134,8 +133,7 @@ int rtas_write_config(struct pci_dn *pdn, int where, int size, u32 val) 
	if (!config_access_valid(pdn, where))

		return PCIBIOS_BAD_REGISTER_NUMBER;



	addr = ((where & 0xf00) << 20) | (pdn->busno << 16) |

		(pdn->devfn << 8) | (where & 0xff);

	addr = rtas_config_addr(pdn->busno, pdn->devfn, where);

	buid = pdn->phb->buid;

	if (buid) {

		ret = rtas_call(ibm_write_pci_config, 5, 1, NULL, addr,

include/asm-powerpc/rtas.h

+16 −0
Original line number Diff line number Diff line
@@ -230,5 +230,21 @@ extern unsigned long rtas_rmo_buf; 


#define GLOBAL_INTERRUPT_QUEUE 9005



/**

 * rtas_config_addr - Format a busno, devfn and reg for RTAS.

 * @busno: The bus number.

 * @devfn: The device and function number as encoded by PCI_DEVFN().

 * @reg: The register number.

 *

 * This function encodes the given busno, devfn and register number as

 * required for RTAS calls that take a "config_addr" parameter.

 * See PAPR requirement 7.3.4-1 for more info.

 */

static inline u32 rtas_config_addr(int busno, int devfn, int reg)

{

	return ((reg & 0xf00) << 20) | ((busno & 0xff) << 16) |

			(devfn << 8) | (reg & 0xff);

}



#endif /* __KERNEL__ */

#endif /* _POWERPC_RTAS_H */

CRA Git | Maintained and supported by SUSTech CRA and CCSE