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powerpc/pseries: Force 32 bit MSIs for devices that require it

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The following patch implements a new PAPR change which allows
the OS to force the use of 32 bit MSIs, regardless of what
the PCI capabilities indicate. This is required for some
devices that advertise support for 64 bit MSIs but don't
actually support them.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Brian King 2013-05-03 11:30:59 +00:00 committed by Benjamin Herrenschmidt
parent c2fd22df89
commit e61133dda4
2 changed files with 20 additions and 3 deletions
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2
arch/powerpc/include/asm/pci-bridge.h
View file

@ -163,6 +163,8 @@ struct pci_dn {
int pci_ext_config_space; /* for pci devices */
int force_32bit_msi:1;
struct pci_dev *pcidev; /* back-pointer to the pci device */
#ifdef CONFIG_EEH
struct eeh_dev *edev; /* eeh device */

21
arch/powerpc/platforms/pseries/msi.c
View file

@ -24,6 +24,7 @@ static int query_token, change_token;
#define RTAS_RESET_FN 2
#define RTAS_CHANGE_MSI_FN 3
#define RTAS_CHANGE_MSIX_FN 4
#define RTAS_CHANGE_32MSI_FN 5
static struct pci_dn *get_pdn(struct pci_dev *pdev)
{
@ -58,7 +59,8 @@ static int rtas_change_msi(struct pci_dn *pdn, u32 func, u32 num_irqs)
seq_num = 1;
do {
if (func == RTAS_CHANGE_MSI_FN || func == RTAS_CHANGE_MSIX_FN)
if (func == RTAS_CHANGE_MSI_FN || func == RTAS_CHANGE_MSIX_FN ||
func == RTAS_CHANGE_32MSI_FN)
rc = rtas_call(change_token, 6, 4, rtas_ret, addr,
BUID_HI(buid), BUID_LO(buid),
func, num_irqs, seq_num);
@ -426,9 +428,12 @@ static int rtas_setup_msi_irqs(struct pci_dev *pdev, int nvec_in, int type)
*/
again:
if (type == PCI_CAP_ID_MSI) {
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
if (pdn->force_32bit_msi)
rc = rtas_change_msi(pdn, RTAS_CHANGE_32MSI_FN, nvec);
else
rc = rtas_change_msi(pdn, RTAS_CHANGE_MSI_FN, nvec);
if (rc < 0) {
if (rc < 0 && !pdn->force_32bit_msi) {
pr_debug("rtas_msi: trying the old firmware call.\n");
rc = rtas_change_msi(pdn, RTAS_CHANGE_FN, nvec);
}
@ -512,3 +517,13 @@ static int rtas_msi_init(void)
return 0;
}
arch_initcall(rtas_msi_init);
static void quirk_radeon(struct pci_dev *dev)
{
struct pci_dn *pdn = get_pdn(dev);
if (pdn)
pdn->force_32bit_msi = 1;
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x68f2, quirk_radeon);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0xaa68, quirk_radeon);