Re: [PATCH v2 4/9] memory: Add STM32 Octo Memory Manager driver

[Patrice CHOTARD <patrice.chotard@foss.st.com>]

On 1/28/25 10:17, Philipp Zabel wrote:
> On Di, 2025-01-28 at 09:17 +0100, patrice.chotard@foss.st.com wrote:
>> From: Patrice Chotard <patrice.chotard@foss.st.com>
>>
>> Octo Memory Manager driver (OMM) manages:
>>   - the muxing between 2 OSPI busses and 2 output ports.
>>     There are 4 possible muxing configurations:
>>       - direct mode (no multiplexing): OSPI1 output is on port 1 and OSPI2
>>         output is on port 2
>>       - OSPI1 and OSPI2 are multiplexed over the same output port 1
>>       - swapped mode (no multiplexing), OSPI1 output is on port 2,
>>         OSPI2 output is on port 1
>>       - OSPI1 and OSPI2 are multiplexed over the same output port 2
>>   - the split of the memory area shared between the 2 OSPI instances.
>>   - chip select selection override.
>>   - the time between 2 transactions in multiplexed mode.
>>   - check firewall access.
>>
>> Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
>> Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
>> ---
>>  drivers/memory/Kconfig     |  17 ++
>>  drivers/memory/Makefile    |   1 +
>>  drivers/memory/stm32_omm.c | 509 +++++++++++++++++++++++++++++++++++++
>>  3 files changed, 527 insertions(+)
>>  create mode 100644 drivers/memory/stm32_omm.c
>>
> [...]
>> diff --git a/drivers/memory/stm32_omm.c b/drivers/memory/stm32_omm.c
>> new file mode 100644
>> index 000000000000..6f20fe0183ec
>> --- /dev/null
>> +++ b/drivers/memory/stm32_omm.c
>> @@ -0,0 +1,509 @@
> [...]
>> +static int stm32_omm_configure(struct device *dev)
>> +{
>> +	struct stm32_omm *omm = dev_get_drvdata(dev);
>> +	struct reset_control *rstc;
>> +	unsigned long clk_rate, clk_rate_max = 0;
>> +	int ret;
>> +	u8 i;
>> +	u32 mux = 0;
>> +	u32 cssel_ovr = 0;
>> +	u32 req2ack = 0;
>> +
>> +	omm->clk = devm_clk_get(dev, NULL);
>> +	if (IS_ERR(omm->clk)) {
>> +		dev_err(dev, "Failed to get OMM clock (%ld)\n",
>> +			PTR_ERR(omm->clk));
>> +
>> +		return PTR_ERR(omm->clk);
>> +	}
>> +
>> +	ret = pm_runtime_resume_and_get(dev);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* parse children's clock */
>> +	for (i = 0; i < omm->nb_child; i++) {
>> +		clk_rate = clk_get_rate(omm->child[i].clk);
>> +		if (!clk_rate) {
>> +			dev_err(dev, "Invalid clock rate\n");
>> +			goto err_clk_disable;
>> +		}
>> +
>> +		if (clk_rate > clk_rate_max)
>> +			clk_rate_max = clk_rate;
>> +	}
>> +
>> +	rstc = devm_reset_control_get_optional(dev, NULL);
> 
> Please use devm_reset_control_get_optional_exclusive() directly.

ok

Thanks
Patrice

> 
> regards
> Philipp