powerpc/85xx: workaround for chips with MSI hardware errata

The MPIC version 2.0 has a MSI errata (errata PIC1 of mpc8544), It causes
that neither MSI nor MSI-X can work fine. This is a workaround to allow
MSI-X to function properly.

Signed-off-by: Liu Shuo <soniccat.liu@gmail.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Jia Hongtao <hongtao.jia@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This commit is contained in:
Hongtao Jia 2015-02-26 15:23:08 +08:00 committed by Scott Wood
parent 807d38b73b
commit ff015659b6
2 changed files with 28 additions and 3 deletions

View File

@ -162,7 +162,17 @@ static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
msg->address_lo = lower_32_bits(address);
msg->address_hi = upper_32_bits(address);
msg->data = hwirq;
/*
* MPIC version 2.0 has erratum PIC1. It causes
* that neither MSI nor MSI-X can work fine.
* This is a workaround to allow MSI-X to function
* properly. It only works for MSI-X, we prevent
* MSI on buggy chips in fsl_setup_msi_irqs().
*/
if (msi_data->feature & MSI_HW_ERRATA_ENDIAN)
msg->data = __swab32(hwirq);
else
msg->data = hwirq;
pr_debug("%s: allocated srs: %d, ibs: %d\n", __func__,
(hwirq >> msi_data->srs_shift) & MSI_SRS_MASK,
@ -180,8 +190,16 @@ static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
struct msi_msg msg;
struct fsl_msi *msi_data;
if (type == PCI_CAP_ID_MSIX)
pr_debug("fslmsi: MSI-X untested, trying anyway.\n");
if (type == PCI_CAP_ID_MSI) {
/*
* MPIC version 2.0 has erratum PIC1. For now MSI
* could not work. So check to prevent MSI from
* being used on the board with this erratum.
*/
list_for_each_entry(msi_data, &msi_head, list)
if (msi_data->feature & MSI_HW_ERRATA_ENDIAN)
return -EINVAL;
}
/*
* If the PCI node has an fsl,msi property, then we need to use it
@ -446,6 +464,11 @@ static int fsl_of_msi_probe(struct platform_device *dev)
msi->feature = features->fsl_pic_ip;
/* For erratum PIC1 on MPIC version 2.0*/
if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) == FSL_PIC_IP_MPIC
&& (fsl_mpic_primary_get_version() == 0x0200))
msi->feature |= MSI_HW_ERRATA_ENDIAN;
/*
* Remember the phandle, so that we can match with any PCI nodes
* that have an "fsl,msi" property.

View File

@ -27,6 +27,8 @@
#define FSL_PIC_IP_IPIC 0x00000002
#define FSL_PIC_IP_VMPIC 0x00000003
#define MSI_HW_ERRATA_ENDIAN 0x00000010
struct fsl_msi_cascade_data;
struct fsl_msi {