Re: [PATCH v13 15/21] PCI: microchip: Add event irqchip field to host port and add PLDA irqchip

[Minda Chen <minda.chen@starfivetech.com>]

On 2023/12/21 23:32, Lorenzo Pieralisi wrote:
> On Thu, Dec 21, 2023 at 06:56:22PM +0800, Minda Chen wrote:
>> 
>> 
>> On 2023/12/14 15:28, Minda Chen wrote:
>> > PolarFire PCIE event IRQs includes PLDA local interrupts and PolarFire
>> > their own IRQs. PolarFire PCIe event irq_chip ops using an event_desc to
>> > unify different IRQ register addresses. On PLDA sides, PLDA irqchip codes
>> > only require to set PLDA local interrupt register. So the PLDA irqchip ops
>> > codes can not be extracted from PolarFire codes.
>> > 
>> > To support PLDA its own event IRQ process, implements PLDA irqchip ops and
>> > add event irqchip field to struct pcie_plda_rp.
>> > 
>> > Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
>> > ---
>> >  .../pci/controller/plda/pcie-microchip-host.c | 65 ++++++++++++++++++-
>> >  drivers/pci/controller/plda/pcie-plda.h       |  3 +
>> >  2 files changed, 67 insertions(+), 1 deletion(-)
>> > 
>> Hi Conor
>>    Could you take time to review this patch?  For I using event irq chip instead of event ops and the whole patch have been changed.  I think it's better 
>>    And I added the implementation of PLDA event irqchip  and make it easier to claim the necessity of the modification.
>>    If you approve this, I will add back the review tag. Thanks
>> 
>> Hi Lorenzo
>>    Have you reviewed this patch？ Does the commit message and the codes are can be approved ？Thanks
>> 
> 
> Please wrap the lines at 75 columns in length.
> 
OK
> I have not reviewed but I am still struggling to understand the
> commit log, I apologise, I can try to review the series and figure
> out what the patch is doing but I would appreciate if commits logs
> could be made easier to parse.
> 
> Thanks,
> Lorenzo
> 

The commit message it is not good.

I draw a graph about the PCIe global event interrupt domain
(related to patch 10- 16).
Actually all these interrupts patches are for extracting the common 
PLDA codes to pcie-plda-host.c and do not change microchip's codes logic.
  
            +----------------------------------------------------------+
            |    microchip  Global event interrupt domain              |
            +-----------------------------------+-----------+----------+
            |                                   | microchip | PLDA     |
            |                                   | event num |(StarFive)|
            |                                   |           |event num |
            +-----------------------------------+-----------+----------+
            |                                   | 0         |          |
            |                                   |           |          |
(mc pcie    |microchip platform event interrupt |           |          |
int line)   |                                   |           |          |
------------|                                   |           |          |
            |                                   |10         |          |
            +-----------------------------------+-----------+----------+
            | PLDA host DMA interrupt           |11         |          |
            | (int number is not fixed, defined |           |          |
            |  by vendor)                       |14         |          |
         +--+-----------------------------------+---------- +----------+-+
         |  |  PLDA event interrupt             |15         |0         | |
         |  |  (int number is fixed)            |           |          | |
---------|--|                                   |           |          | |
(Starfive|  |                                   |           |          | |
pcie int |  |   +------------------+            |           |          | |
line)    |  |   |INTx event domain |            |           |          | |
         |  |   +------------------+            |           |          | |
         |  |                                   |           |          | |
         |  |   +------------------+            |           |          | |
         |  |   |MSI event domain  |            |           |          | |
         |  |   +------------------+            |           |          | |
         |  |                                   |27         |12        | |
         |  +---------------------------------+-+-----------+----------+ |
         | extract PLDA event part to common PLDA file.                  |
         +---------------------------------------------------------------+


>> > diff --git a/drivers/pci/controller/plda/pcie-microchip-host.c b/drivers/pci/controller/plda/pcie-microchip-host.c
>> > index fd0d92c3d03f..ff40c1622173 100644
>> > --- a/drivers/pci/controller/plda/pcie-microchip-host.c
>> > +++ b/drivers/pci/controller/plda/pcie-microchip-host.c
>> > @@ -771,6 +771,63 @@ static struct irq_chip mc_event_irq_chip = {
>> >  	.irq_unmask = mc_unmask_event_irq,
>> >  };
>> > > +static u32 plda_hwirq_to_mask(int hwirq)
>> > +{
>> > +	u32 mask;
>> > +
>> > +	if (hwirq < EVENT_PM_MSI_INT_INTX)
>> > +		mask = BIT(hwirq + A_ATR_EVT_POST_ERR_SHIFT);
>> > +	else if (hwirq == EVENT_PM_MSI_INT_INTX)
>> > +		mask = PM_MSI_INT_INTX_MASK;
>> > +	else
>> > +		mask = BIT(hwirq + PM_MSI_TO_MASK_OFFSET);
>> > +
>> > +	return mask;
>> > +}
>> > +
>> > +static void plda_ack_event_irq(struct irq_data *data)
>> > +{
>> > +	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
>> > +
>> > +	writel_relaxed(plda_hwirq_to_mask(data->hwirq),
>> > +		       port->bridge_addr + ISTATUS_LOCAL);
>> > +}
>> > +
>> > +static void plda_mask_event_irq(struct irq_data *data)
>> > +{
>> > +	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
>> > +	u32 mask, val;
>> > +
>> > +	mask = plda_hwirq_to_mask(data->hwirq);
>> > +
>> > +	raw_spin_lock(&port->lock);
>> > +	val = readl_relaxed(port->bridge_addr + IMASK_LOCAL);
>> > +	val &= ~mask;
>> > +	writel_relaxed(val, port->bridge_addr + IMASK_LOCAL);
>> > +	raw_spin_unlock(&port->lock);
>> > +}
>> > +
>> > +static void plda_unmask_event_irq(struct irq_data *data)
>> > +{
>> > +	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
>> > +	u32 mask, val;
>> > +
>> > +	mask = plda_hwirq_to_mask(data->hwirq);
>> > +
>> > +	raw_spin_lock(&port->lock);
>> > +	val = readl_relaxed(port->bridge_addr + IMASK_LOCAL);
>> > +	val |= mask;
>> > +	writel_relaxed(val, port->bridge_addr + IMASK_LOCAL);
>> > +	raw_spin_unlock(&port->lock);
>> > +}
>> > +
>> > +static struct irq_chip plda_event_irq_chip = {
>> > +	.name = "PLDA PCIe EVENT",
>> > +	.irq_ack = plda_ack_event_irq,
>> > +	.irq_mask = plda_mask_event_irq,
>> > +	.irq_unmask = plda_unmask_event_irq,
>> > +};
>> > +
>> >  static const struct plda_event_ops plda_event_ops = {
>> >  	.get_events = plda_get_events,
>> >  };
>> > @@ -778,7 +835,9 @@ static const struct plda_event_ops plda_event_ops = {
>> >  static int plda_pcie_event_map(struct irq_domain *domain, unsigned int irq,
>> >  			       irq_hw_number_t hwirq)
>> >  {
>> > -	irq_set_chip_and_handler(irq, &mc_event_irq_chip, handle_level_irq);
>> > +	struct plda_pcie_rp *port = (void *)domain->host_data;
>> > +
>> > +	irq_set_chip_and_handler(irq, port->event_irq_chip, handle_level_irq);
>> >  	irq_set_chip_data(irq, domain->host_data);
>> >  
>> >  	return 0;
>> > @@ -963,6 +1022,9 @@ static int plda_init_interrupts(struct platform_device *pdev,
>> >  	if (!port->event_ops)
>> >  		port->event_ops = &plda_event_ops;
>> >  
>> > +	if (!port->event_irq_chip)
>> > +		port->event_irq_chip = &plda_event_irq_chip;
>> > +
>> >  	ret = plda_pcie_init_irq_domains(port);
>> >  	if (ret) {
>> >  		dev_err(dev, "failed creating IRQ domains\n");
>> > @@ -1040,6 +1102,7 @@ static int mc_platform_init(struct pci_config_window *cfg)
>> >  		return ret;
>> >  
>> >  	port->plda.event_ops = &mc_event_ops;
>> > +	port->plda.event_irq_chip = &mc_event_irq_chip;
>> >  
>> >  	/* Address translation is up; safe to enable interrupts */
>> >  	ret = plda_init_interrupts(pdev, &port->plda, &mc_event);
>> > diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
>> > index dd8bc2750bfc..24ac50c458dc 100644
>> > --- a/drivers/pci/controller/plda/pcie-plda.h
>> > +++ b/drivers/pci/controller/plda/pcie-plda.h
>> > @@ -128,6 +128,8 @@
>> >   * DMA end : reserved for vendor implement
>> >   */
>> >  
>> > +#define PM_MSI_TO_MASK_OFFSET			19
>> > +
>> >  struct plda_pcie_rp;
>> >  
>> >  struct plda_event_ops {
>> > @@ -150,6 +152,7 @@ struct plda_pcie_rp {
>> >  	raw_spinlock_t lock;
>> >  	struct plda_msi msi;
>> >  	const struct plda_event_ops *event_ops;
>> > +	const struct irq_chip *event_irq_chip;
>> >  	void __iomem *bridge_addr;
>> >  	int num_events;
>> >  };