Re: [PATCH v3 01/18] irqchip: Add IMS (Interrupt Message Storage) driver

[Dey, Megha]

Hi Thomas,

On 9/30/2020 11:23 AM, Thomas Gleixner wrote:
> On Tue, Sep 15 2020 at 16:27, Dave Jiang wrote:
> > From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > +config IMS_MSI_ARRAY
> > +	bool "IMS Interrupt Message Storm MSI controller for device memory storage arrays"
> Hehe, you missed a Message Storm :)
i will change this in the next version
> > +	depends on PCI
> > +	select IMS_MSI
> > +	select GENERIC_MSI_IRQ_DOMAIN
> > +	help
> > +	  Support for IMS Interrupt Message Storm MSI controller
> and another one.
ok :)
> > +	  with IMS slot storage in a slot array in device memory
> > +
> > +static void ims_array_mask_irq(struct irq_data *data)
> > +{
> > +	struct msi_desc *desc = irq_data_get_msi_desc(data);
> > +	struct ims_slot __iomem *slot = desc->device_msi.priv_iomem;
> > +	u32 __iomem *ctrl = &slot->ctrl;
> > +
> > +	iowrite32(ioread32(ctrl) | IMS_VECTOR_CTRL_MASK, ctrl);
> > +	ioread32(ctrl); /* Flush write to device */
> Bah, I fundamentaly hate tail comments. They are a distraction and
> disturb the reading flow. Put it above the ioread32() please.
Will do.
> > +static void ims_array_unmask_irq(struct irq_data *data)
> > +{
> > +	struct msi_desc *desc = irq_data_get_msi_desc(data);
> > +	struct ims_slot __iomem *slot = desc->device_msi.priv_iomem;
> > +	u32 __iomem *ctrl = &slot->ctrl;
> > +
> > +	iowrite32(ioread32(ctrl) & ~IMS_VECTOR_CTRL_MASK, ctrl);
> Why is this one not flushed?
I will add it.
> > +}
> > +
> > +static void ims_array_write_msi_msg(struct irq_data *data, struct msi_msg *msg)
> > +{
> > +	struct msi_desc *desc = irq_data_get_msi_desc(data);
> > +	struct ims_slot __iomem *slot = desc->device_msi.priv_iomem;
> > +
> > +	iowrite32(msg->address_lo, &slot->address_lo);
> > +	iowrite32(msg->address_hi, &slot->address_hi);
> > +	iowrite32(msg->data, &slot->data);
> > +	ioread32(slot);
> Yuck? slot points to the struct and just because ioread32() accepts a
> void pointer does not make it any more readable.
hmm ok , will change this.
> > +static void ims_array_reset_slot(struct ims_slot __iomem *slot)
> > +{
> > +	iowrite32(0, &slot->address_lo);
> > +	iowrite32(0, &slot->address_hi);
> > +	iowrite32(0, &slot->data);
> > +	iowrite32(0, &slot->ctrl);
> Flush?

ok!

-Megha

> Thanks,
>
>          tglx