| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <9c5e5c33-9fac-4240-8e30-de401e781324@ti.com>
Date: Wed, 11 Sep 2024 09:34:11 -0500
From: Judith Mendez <jm@...com>
To: Adrian Hunter <adrian.hunter@...el.com>,
Ulf Hansson
<ulf.hansson@...aro.org>
CC: <linux-mmc@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v1] mmc: sdhci_am654: Add
sdhci_am654_start_signal_voltage_switch
Hi Adrian,
On 9/11/24 12:17 AM, Adrian Hunter wrote:
> On 11/09/24 02:22, Judith Mendez wrote:
>> Hi Adrian,
>>
>> On 9/10/24 12:10 PM, Adrian Hunter wrote:
>>> On 10/09/24 17:30, Judith Mendez wrote:
>>>> Hi Adrian,
>>>>
>>>> On 9/9/24 1:26 AM, Adrian Hunter wrote:
>>>>> On 6/09/24 20:50, Judith Mendez wrote:
>>>>>> The sdhci_start_signal_voltage_switch function sets
>>>>>> V1P8_SIGNAL_ENA by default after switching to 1v8 signaling.
>>>>>> V1P8_SIGNAL_ENA determines whether to launch cmd/data on neg
>>>>>> edge or pos edge of clock.
>>>>>>
>>>>>> Due to some eMMC and SD failures seen across am62x platform,
>>>>>> do not set V1P8_SIGNAL_ENA by default, only enable the bit
>>>>>> for devices that require this bit in order to switch to 1v8
>>>>>> voltage for uhs modes.
>>>>>>
>>>>>> Signed-off-by: Judith Mendez <jm@...com>
>>>>>> ---
>>>>>> drivers/mmc/host/sdhci_am654.c | 86 ++++++++++++++++++++++++++++++++++
>>>>>> 1 file changed, 86 insertions(+)
>>>>>>
>>>>>> diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
>>>>>> index 0aa3c40ea6ed8..fb6232e56606b 100644
>>>>>> --- a/drivers/mmc/host/sdhci_am654.c
>>>>>> +++ b/drivers/mmc/host/sdhci_am654.c
>>>>>> @@ -155,6 +155,7 @@ struct sdhci_am654_data {
>>>>>> u32 tuning_loop;
>>>>>> #define SDHCI_AM654_QUIRK_FORCE_CDTEST BIT(0)
>>>>>> +#define SDHCI_AM654_QUIRK_SET_V1P8_ENA BIT(1)
>>>>>
>>>>> It would be better for the quirk to represent the deviation
>>>>> from normal i.e.
>>>>>
>>>>> #define SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA BIT(1)
>>>>>
>>>>>> };
>>>>>> struct window {
>>>>>> @@ -356,6 +357,79 @@ static void sdhci_j721e_4bit_set_clock(struct sdhci_host *host,
>>>>>> sdhci_set_clock(host, clock);
>>>>>> }
>>>>>> +int sdhci_am654_start_signal_voltage_switch(struct mmc_host *mmc,
>>>>>> + struct mmc_ios *ios)
>>>>>
>>>>> Simpler to call sdhci_start_signal_voltage_switch() for the normal
>>>>> case e.g.
>>>>
>>>> This is simpler, so sure will use thanks.
>>>>
>>>>>
>>>>> static int sdhci_am654_start_signal_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
>>>>> {
>>>>> struct sdhci_host *host = mmc_priv(mmc);
>>>>> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>> struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
>>>>>
>>>>>
>>>>> if ((sdhci_am654->quirks & SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA) &&
>>>>> ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
>>>>> ret = mmc_regulator_set_vqmmc(mmc, ios);
>>>>> if (ret < 0) {
>>>>> pr_warn("%s: Switching to 1.8V signalling voltage failed\n",
>>>>> mmc_hostname(mmc));
>>>>> return -EIO;
>>>>> }
>>>>> return 0;
>>>>> }
>>>>>
>>>>> return sdhci_start_signal_voltage_switch(mmc, ios);
>>>>> }
>>>>>
>>>>>> +{
>>>>>> + struct sdhci_host *host = mmc_priv(mmc);
>>>>>> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>>> + struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
>>>>>> + u16 ctrl;
>>>>>> + int ret;
>>>>>> +
>>>>>> + if (host->version < SDHCI_SPEC_300)
>>>>>> + return 0;
>>>>>> +
>>>>>> + switch (ios->signal_voltage) {
>>>>>> + case MMC_SIGNAL_VOLTAGE_330:
>>>>>> + if (!(host->flags & SDHCI_SIGNALING_330))
>>>>>> + return -EINVAL;
>>>>>> +
>>>>>> + ctrl &= ~SDHCI_CTRL_VDD_180;
>>>>>> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
>>>>>> +
>>>>>> + if (!IS_ERR(mmc->supply.vqmmc)) {
>>>>>> + ret = mmc_regulator_set_vqmmc(mmc, ios);
>>>>>> + if (ret < 0) {
>>>>>> + pr_warn("%s: Switching to 3.3V signalling voltage failed\n",
>>>>>> + mmc_hostname(mmc));
>>>>>> + return -EIO;
>>>>>> + }
>>>>>> + }
>>>>>> +
>>>>>> + usleep_range(5000, 5500);
>>>>>> +
>>>>>> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>>>>> + if (!(ctrl & SDHCI_CTRL_VDD_180))
>>>>>> + return 0;
>>>>>> +
>>>>>> + pr_warn("%s: 3.3V regulator output did not become stable\n",
>>>>>> + mmc_hostname(mmc));
>>>>>> +
>>>>>> + return -EAGAIN;
>>>>>> +
>>>>>> + case MMC_SIGNAL_VOLTAGE_180:
>>>>>> + if (!(host->flags & SDHCI_SIGNALING_180))
>>>>>> + return -EINVAL;
>>>>>> +
>>>>>> + if (!IS_ERR(mmc->supply.vqmmc)) {
>>>>>> + ret = mmc_regulator_set_vqmmc(mmc, ios);
>>>>>> + if (ret < 0) {
>>>>>> + pr_warn("%s: Switching to 1.8V signalling voltage failed\n",
>>>>>> + mmc_hostname(mmc));
>>>>>> + return -EIO;
>>>>>> + }
>>>>>> + }
>>>>>> +
>>>>>> + if (sdhci_am654->quirks & SDHCI_AM654_QUIRK_SET_V1P8_ENA) {
>>>>>> + ctrl |= SDHCI_CTRL_VDD_180;
>>>>>> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
>>>>>> +
>>>>>> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>>>>> + if (ctrl & SDHCI_CTRL_VDD_180)
>>>>>> + return 0;
>>>>>> +
>>>>>> + pr_warn("%s: 1.8V regulator output did not become stable\n",
>>>>>> + mmc_hostname(mmc));
>>>>>> +
>>>>>> + return -EAGAIN;
>>>>>> + }
>>>>>> + return 0;
>>>>>> +
>>>>>> + default:
>>>>>> + return 0;
>>>>>> + }
>>>>>> +}
>>>>>> +
>>>>>> static u8 sdhci_am654_write_power_on(struct sdhci_host *host, u8 val, int reg)
>>>>>> {
>>>>>> writeb(val, host->ioaddr + reg);
>>>>>> @@ -801,6 +875,8 @@ static int sdhci_am654_get_of_property(struct platform_device *pdev,
>>>>>> struct sdhci_am654_data *sdhci_am654)
>>>>>> {
>>>>>> struct device *dev = &pdev->dev;
>>>>>> + struct device_node *np = dev->of_node;
>>>>>> + struct device_node *node;
>>>>>> int drv_strength;
>>>>>> int ret;
>>>>>> @@ -844,6 +920,15 @@ static int sdhci_am654_get_of_property(struct platform_device *pdev,
>>>>>> if (device_property_read_bool(dev, "ti,fails-without-test-cd"))
>>>>>> sdhci_am654->quirks |= SDHCI_AM654_QUIRK_FORCE_CDTEST;
>>>>>> + node = of_parse_phandle(np, "vmmc-supply", 0);
>>>>>> +
>>>>>> + if (node) {
>>>>>> + node = of_parse_phandle(np, "vqmmc-supply", 0);
>>>>>> +
>>>>>> + if (!node)
>>>>>> + sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SET_V1P8_ENA;
>>>>>> + }
>>>>>
>>>>> It would be simpler without 'np' and 'node'. Not sure
>>>>> what the rule is meant to be, but it could be something like:
>>>>>
>>>>> if (of_parse_phandle(dev->of_node, "vmmc-supply", 0) &&
>>>>> of_parse_phandle(dev->of_node, "vqmmc-supply", 0)
>>>>> sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA;
>>>>
>>>> My issue with this is that I also need the quirk (SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA) for eMMC. DT node for eMMC does
>>>> not include vmmc and vqmmc supplies. That is why I had the quirk logic
>>>> inverted.
>>>
>>> Ideally there would be a more direct way to distinguish eMMC, but
>>> otherwise, having both supplies or neither would be:
>>>
>>> if (!!of_parse_phandle(dev->of_node, "vmmc-supply", 0) ==
>>> !!of_parse_phandle(dev->of_node, "vqmmc-supply", 0))
>>> sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA;
>>
>>
>> Not sure I love the double NOT, but ok, I can use this, will fix for v2.
>
> It could use a comment, including about the eMMC thing.
Sure, will add. Thanks.
>
>>
>> Thanks for your suggestion!
>>
>> ~ Judith
>>
>>>
>>>
>>>>
>>>> This patch fixes timing issues with both eMMC and SD. (:
>>>>
>>>> ~ Judith
>>>>
>>>>
>>>>>
>>>>>> +
>>>>>> sdhci_get_of_property(pdev);
>>>>>> return 0;
>>>>>> @@ -940,6 +1025,7 @@ static int sdhci_am654_probe(struct platform_device *pdev)
>>>>>> goto err_pltfm_free;
>>>>>> }
>>>>>> + host->mmc_host_ops.start_signal_voltage_switch = sdhci_am654_start_signal_voltage_switch;
>>>>>> host->mmc_host_ops.execute_tuning = sdhci_am654_execute_tuning;
>>>>>> pm_runtime_get_noresume(dev);
>>>>>>
>>>>>> base-commit: cf6444ba528f043398b112ac36e041a4d8685cb1
>>>>>
>>>>>
>>>>
>>>
>>
>
Powered by blists - more mailing lists