On Fri, Apr 12, 2019 at 08:36:12AM +0000, Z.q. Hou wrote:
> From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
>
> In the loop block, there is not code to update the loop key,
> this patch updates the loop key by re-read the INTx status
> register.
>
> This patch also add the clearing of the handled INTx status.
>
> Note: Need MV to test this fix.
This means INTX were never tested and current code handling them is,
AFAICS, an infinite loop which is very very bad.
This is a gross bug and must be fixed as soon as possible.
I want Karthikeyan ACK and Tested-by on this patch.
Lorenzo
> Fixes: 9af6bcb11e12 ("PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP driver")
> Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
> Reviewed-by: Minghuan Lian <Minghuan.Lian@xxxxxxx>
> Reviewed-by: Subrahmanya Lingappa <l.subrahmanya@xxxxxxxxxxxxxx>
> ---
> V5:
> - Corrected and retouched the subject and changelog.
>
> drivers/pci/controller/pcie-mobiveil.c | 13 +++++++++----
> 1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-mobiveil.c b/drivers/pci/controller/pcie-mobiveil.c
> index 4ba458474e42..78e575e71f4d 100644
> --- a/drivers/pci/controller/pcie-mobiveil.c
> +++ b/drivers/pci/controller/pcie-mobiveil.c
> @@ -361,6 +361,7 @@ static void mobiveil_pcie_isr(struct irq_desc *desc)
> /* Handle INTx */
> if (intr_status & PAB_INTP_INTX_MASK) {
> shifted_status = csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
> + shifted_status &= PAB_INTP_INTX_MASK;
> shifted_status >>= PAB_INTX_START;
> do {
> for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
> @@ -372,12 +373,16 @@ static void mobiveil_pcie_isr(struct irq_desc *desc)
> dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
> bit);
>
> - /* clear interrupt */
> - csr_writel(pcie,
> - shifted_status << PAB_INTX_START,
> + /* clear interrupt handled */
> + csr_writel(pcie, 1 << (PAB_INTX_START + bit),
> PAB_INTP_AMBA_MISC_STAT);
> }
> - } while ((shifted_status >> PAB_INTX_START) != 0);
> +
> + shifted_status = csr_readl(pcie,
> + PAB_INTP_AMBA_MISC_STAT);
> + shifted_status &= PAB_INTP_INTX_MASK;
> + shifted_status >>= PAB_INTX_START;
> + } while (shifted_status != 0);
> }
>
> /* read extra MSI status register */
> --
> 2.17.1
>
