[Skiboot] [PATCH] hw/imc: Check ucode state in all the chip

[Madhavan Srinivasan]

On Friday 01 December 2017 11:06 AM, Stewart Smith wrote:
> Madhavan Srinivasan <maddy at linux.vnet.ibm.com> writes:
>> disable_unavailable_units() checks whether the ucode
>> is in the running state before enabling the nest units
>> in the device tree. From a recent debug, it is found
>> that on some system boot, ucode is not loaded and
>> running in all the chips in the system. And this
>> caused a fail in OPAL_IMC_COUNTERS_STOP call where
>> we check for ucode state on each chip. Bug here is
>> that disable_unavailable_units() checks the state
>> of the ucode only in boot cpu chip. Patch adds a
>> condition in disable_unavailable_units() to check
>> for the ucode state in all the chip before enabling
>> the nest units in the device tree node.
>>
>> Fixes: f98d59958db19 ('skiboot: Find the IMC DTB')
>> Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
>> ---
>>   hw/imc.c | 15 ++++++++++++++-
>>   1 file changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/imc.c b/hw/imc.c
>> index 88d0302d9da6..1db94ec6ac1b 100644
>> --- a/hw/imc.c
>> +++ b/hw/imc.c
>> @@ -320,10 +320,23 @@ static void disable_unavailable_units(struct dt_node *dev)
>>   	struct imc_chip_cb *cb;
>>   	struct dt_node *target;
>>   	int i;
>> +	bool flag = true;
>> +	struct proc_chip *chip;
>> +
>> +	/*
>> +	 * Check the state of ucode in all the chip.
>> +	 * Disable the nest unit if ucode is not initialized
>> +	 * in any of the chip.
>> +	 */
>> +	for_each_chip(chip) {
>> +		cb = get_imc_cb(chip->id);
>> +		if (!cb)
>> +			flag = false;
>> +	}
>>
>>   	/* Fetch the IMC control block structure */
>>   	cb = get_imc_cb(this_cpu()->chip_id);
>> -	if (cb)
>> +	if (cb && flag)
>>   		avl_vec = be64_to_cpu(cb->imc_chip_avl_vector);
>>   	else {
>>   		avl_vec = 0; /* Remove only nest imc device nodes */
> (just confirming what we chatted about on slack), there's a bug here
> where it's not properly handling things unless it's the last chip that
> the ucode isn't running on.
>
> Awaiting v2 :)

Definitely respining the patch. My bad. But nice catch.
Thanks for review comments

Maddy

>