Re: [PATCH] i2c: amd-mp2: use msix/msi if the hardware supports

Shyam Sundar S K
2022-10-28T03:59:18Z

On 10/25/2022 11:41 PM, Raju Rangoju wrote:
> Use msix or msi interrupts if the hardware supports it. Else, fallback to
> legacy interrupts.
>
> Fixes: 529766e0a011 ("i2c: Add drivers for the AMD PCIe MP2 I2C controller")
> Co-developed-by: Basavaraj Natikar <basavaraj.natikar@amd.com>
> Signed-off-by: Basavaraj Natikar <basavaraj.natikar@amd.com>
> Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>

Looks good to me.

Acked-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>

> ---
> drivers/i2c/busses/i2c-amd-mp2-pci.c | 30 +++++++++++++++++++---------
> drivers/i2c/busses/i2c-amd-mp2.h | 1 +
> 2 files changed, 22 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-amd-mp2-pci.c b/drivers/i2c/busses/i2c-amd-mp2-pci.c
> index f57077a7448d..143165300949 100644
> --- a/drivers/i2c/busses/i2c-amd-mp2-pci.c
> +++ b/drivers/i2c/busses/i2c-amd-mp2-pci.c
> @@ -288,7 +288,7 @@ static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata)
> static int amd_mp2_pci_init(struct amd_mp2_dev *privdata,
> struct pci_dev *pci_dev)
> {
> - int rc;
> + int irq_flag = 0, rc;
>
> pci_set_drvdata(pci_dev, privdata);
>
> @@ -311,17 +311,29 @@ static int amd_mp2_pci_init(struct amd_mp2_dev *privdata,
> if (rc)
> goto err_dma_mask;
>
> - /* Set up intx irq */
> + /* request and enable interrupt */
> writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
> - pci_intx(pci_dev, 1);
> - rc = devm_request_irq(&pci_dev->dev, pci_dev->irq, amd_mp2_irq_isr,
> - IRQF_SHARED, dev_name(&pci_dev->dev), privdata);
> - if (rc)
> - pci_err(pci_dev, "Failure requesting irq %i: %d\n",
> - pci_dev->irq, rc);
> + rc = pci_alloc_irq_vectors(pci_dev, 1, 1, PCI_IRQ_ALL_TYPES);
> + if (rc < 0) {
> + dev_err(&pci_dev->dev, "Failed to allocate single IRQ err=%d\n", rc);
> + goto err_dma_mask;
> + }
> +
> + privdata->dev_irq = pci_irq_vector(pci_dev, 0);
> + if (!pci_dev->msix_enabled && !pci_dev->msi_enabled)
> + irq_flag = IRQF_SHARED;
> +
> + rc = devm_request_irq(&pci_dev->dev, privdata->dev_irq,
> + amd_mp2_irq_isr, irq_flag, dev_name(&pci_dev->dev), privdata);
> + if (rc) {
> + pci_err(pci_dev, "Failure requesting irq %i: %d\n", privdata->dev_irq, rc);
> + goto free_irq_vectors;
> + }
>
> return rc;
>
> +free_irq_vectors:
> + free_irq(privdata->dev_irq, privdata);
> err_dma_mask:
> pci_clear_master(pci_dev);
> err_pci_enable:
> @@ -364,7 +376,7 @@ static void amd_mp2_pci_remove(struct pci_dev *pci_dev)
> pm_runtime_forbid(&pci_dev->dev);
> pm_runtime_get_noresume(&pci_dev->dev);
>
> - pci_intx(pci_dev, 0);
> + free_irq(privdata->dev_irq, privdata);
> pci_clear_master(pci_dev);
>
> amd_mp2_clear_reg(privdata);
> diff --git a/drivers/i2c/busses/i2c-amd-mp2.h b/drivers/i2c/busses/i2c-amd-mp2.h
> index ddecd0c88656..018a42de8b1e 100644
> --- a/drivers/i2c/busses/i2c-amd-mp2.h
> +++ b/drivers/i2c/busses/i2c-amd-mp2.h
> @@ -183,6 +183,7 @@ struct amd_mp2_dev {
> struct mutex c2p_lock;
> u8 c2p_lock_busid;
> unsigned int probed;
> + int dev_irq;
> };
>
> /* PCIe communication driver */
>