[PATCH 07/13] powerpc/xive: Add a debug_show handler to the XIVE irq_domain

[Cédric Le Goater]

On 12/9/20 4:50 PM, Greg Kurz wrote:
> On Tue, 8 Dec 2020 16:11:18 +0100
> Cédric Le Goater <clg at kaod.org> wrote:
> 
>> Full state of the Linux interrupt descriptors can be dumped under
>> debugfs when compiled with CONFIG_GENERIC_IRQ_DEBUGFS. Add support for
>> the XIVE interrupt controller.
>>
>> Signed-off-by: Cédric Le Goater <clg at kaod.org>
>> ---
>>  arch/powerpc/sysdev/xive/common.c | 58 +++++++++++++++++++++++++++++++
>>  1 file changed, 58 insertions(+)
>>
>> diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
>> index 721617f0f854..411cba12d73b 100644
>> --- a/arch/powerpc/sysdev/xive/common.c
>> +++ b/arch/powerpc/sysdev/xive/common.c
>> @@ -1303,11 +1303,69 @@ static int xive_irq_domain_match(struct irq_domain *h, struct device_node *node,
>>  	return xive_ops->match(node);
>>  }
>>  
>> +#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
>> +static const char * const esb_names[] = { "RESET", "OFF", "PENDING", "QUEUED" };
>> +
>> +static const struct {
>> +	u64  mask;
>> +	char *name;
>> +} xive_irq_flags[] = {
>> +	{ XIVE_IRQ_FLAG_STORE_EOI, "STORE_EOI" },
>> +	{ XIVE_IRQ_FLAG_LSI,       "LSI"       },
> 
>> +	{ XIVE_IRQ_FLAG_SHIFT_BUG, "SHIFT_BUG" },
>> +	{ XIVE_IRQ_FLAG_MASK_FW,   "MASK_FW"   },
>> +	{ XIVE_IRQ_FLAG_EOI_FW,    "EOI_FW"    },
> 
> If seems that you don't even need these ^^ if you move this patch after
> patch 11 actually.>
> 
>> +	{ XIVE_IRQ_FLAG_H_INT_ESB, "H_INT_ESB" },
>> +	{ XIVE_IRQ_FLAG_NO_EOI,    "NO_EOI"    },
>> +};
>> +
>> +static void xive_irq_domain_debug_show(struct seq_file *m, struct irq_domain *d,
>> +				       struct irq_data *irqd, int ind)
>> +{
>> +	struct xive_irq_data *xd;
>> +	u64 val;
>> +	int i;
>> +
>> +	/* No IRQ domain level information. To be done */
>> +	if (!irqd)
>> +		return;
>> +
>> +	if (!is_xive_irq(irq_data_get_irq_chip(irqd)))
> 
> Wouldn't it be a bug to get anything else but the XIVE irqchip here ?

no.

> WARN_ON_ONCE() ?

XIVE IPIs are in the same domain but have a different chip. 

C.
 
>> +		return;
>> +
>> +	seq_printf(m, "%*sXIVE:\n", ind, "");
>> +	ind++;
>> +
>> +	xd = irq_data_get_irq_handler_data(irqd);
>> +	if (!xd) {
>> +		seq_printf(m, "%*snot assigned\n", ind, "");
>> +		return;
>> +	}
>> +
>> +	val = xive_esb_read(xd, XIVE_ESB_GET);
>> +	seq_printf(m, "%*sESB:      %s\n", ind, "", esb_names[val & 0x3]);
>> +	seq_printf(m, "%*sPstate:   %s %s\n", ind, "", xd->stale_p ? "stale" : "",
>> +		   xd->saved_p ? "saved" : "");
>> +	seq_printf(m, "%*sTarget:   %d\n", ind, "", xd->target);
>> +	seq_printf(m, "%*sChip:     %d\n", ind, "", xd->src_chip);
>> +	seq_printf(m, "%*sTrigger:  0x%016llx\n", ind, "", xd->trig_page);
>> +	seq_printf(m, "%*sEOI:      0x%016llx\n", ind, "", xd->eoi_page);
>> +	seq_printf(m, "%*sFlags:    0x%llx\n", ind, "", xd->flags);
>> +	for (i = 0; i < ARRAY_SIZE(xive_irq_flags); i++) {
>> +		if (xd->flags & xive_irq_flags[i].mask)
>> +			seq_printf(m, "%*s%s\n", ind + 12, "", xive_irq_flags[i].name);
>> +	}
>> +}
>> +#endif
>> +
>>  static const struct irq_domain_ops xive_irq_domain_ops = {
>>  	.match = xive_irq_domain_match,
>>  	.map = xive_irq_domain_map,
>>  	.unmap = xive_irq_domain_unmap,
>>  	.xlate = xive_irq_domain_xlate,
>> +#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
>> +	.debug_show = xive_irq_domain_debug_show,
>> +#endif
>>  };
>>  
>>  static void __init xive_init_host(struct device_node *np)
>