Adding a .platform_init callback to sdhci_arasan_ops
Sebastian Frias
sf84 at laposte.net
Mon Nov 28 06:39:10 PST 2016
On 28/11/16 14:28, Sebastian Frias wrote:
> On 28/11/16 12:44, Adrian Hunter wrote:
>> On 28/11/16 13:20, Sebastian Frias wrote:
>>> Hi Adrian,
>>>
>>> On 28/11/16 11:30, Adrian Hunter wrote:
>>>> On 28/11/16 09:32, Michal Simek wrote:
>>>>> +Sai for Xilinx perspective.
>>>>>
>>>>> On 25.11.2016 16:24, Sebastian Frias wrote:
>>>>>> Hi,
>>>>>>
>>>>>> When using the Arasan SDHCI HW IP, there is a set of parameters called
>>>>>> "Hardware initialized registers"
>>>>>>
>>>>>> (Table 7, Section "Pin Signals", page 56 of Arasan "SD3.0/SDIO3.0/eMMC4.4
>>>>>> AHB Host Controller", revision 6.0 document)
>>>>>>
>>>>>> In some platforms those signals are connected to registers that need to
>>>>>> be programmed at some point for proper driver/HW initialisation.
>>>>>>
>>>>>> I found that the 'struct sdhci_ops' contains a '.platform_init' callback
>>>>>> that is called from within 'sdhci_pltfm_init', and that seems a good
>>>>>> candidate for a place to program those registers (*).
>>>>>>
>>>>>> Do you agree?
>>>>
>>>> We already killed .platform_init
>>>
>>> I just saw that, yet it was the perfect place for the HW initialisation I'm
>>> talking about.
>>> Any way we can restore it?
>>
>> It doesn't serve any purpose I am aware of.
>
> It would serve (for me) if it was there :-)
>
>>
>>>
>>>>
>>>> What is wrong with sdhci_arasan_probe()?
>>>
>>> Well, in 4.7 sdhci_arasan_probe() did not call of_match_device(), so I had
>>> put a call to it just before sdhci_pltfm_init(), something like:
>>>
>>> +static const struct of_device_id sdhci_arasan_of_match[] = {
>>> + {
>>> + .compatible = "arasan,sdhci-8.9a",
>>> + .data = &sdhci_arasan_ops,
>>> + },
>>> + {
>>> + .compatible = "arasan,sdhci-5.1",
>>> + .data = &sdhci_arasan_ops,
>>> + },
>>> + {
>>> + .compatible = "arasan,sdhci-4.9a",
>>> + .data = &sdhci_arasan_ops,
>>> + },
>>> + {
>>> + .compatible = "sigma,smp8734-sdio",
>>> + .data = &sdhci_arasan_tango4_ops,
>>> + },
>>> + { }
>>> +};
>>> +MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
>>>
>>> ...
>>>
>>> + const struct of_device_id *match;
>>> +
>>> + match = of_match_device(sdhci_arasan_of_match, &pdev->dev);
>>> + if (match)
>>> + sdhci_arasan_pdata.ops = match->data;
>>>
>>> where 'sdhci_arasan_tango4_ops' contained a pointer to a .platform_init
>>> callback.
>>>
>>> However, as I stated earlier, an upstream commit:
>>>
>>> commit 3ea4666e8d429223fbb39c1dccee7599ef7657d5
>>> Author: Douglas Anderson <dianders at chromium.org>
>>> Date: Mon Jun 20 10:56:47 2016 -0700
>>>
>>> mmc: sdhci-of-arasan: Properly set corecfg_baseclkfreq on rk3399
>>>
>>> changed struct 'sdhci_arasan_of_match' to convey different data, which
>>> means that instead of having a generic way of accessing such data (such
>>> as 'of_match_device()' and ".data" field), one must also check for
>>> specific "compatible" strings to make sense of the ".data" field, such as
>>> "rockchip,rk3399-sdhci-5.1"
>>>
>>> With the current code:
>>> - there's no 'of_match_device()' before 'sdhci_pltfm_init()'
>>> - the sdhci_pltfm_init() call is made with a static 'sdhci_arasan_pdata'
>>> struct (so it cannot be made dependent on the "compatible" string).
>>> - since 'sdhci_arasan_pdata' is the same for all compatible devices, even
>>> for those that require special handling, more "compatible" matching code is
>>> required
>>> - leading to spread "compatible" matching code; IMHO it would be cleaner if
>>> the 'sdhci_arasan_probe()' code was generic, with just a generic "compatible"
>>> matching, which then proceeded with specific initialisation and generic
>>> initialisation.
>>>
>>> In a nutshell, IMHO it would be better if adding support for more SoCs only
>>> involved changing just 'sdhci_arasan_of_match' without the need to change
>>> 'sdhci_arasan_probe()'.
>>> That would clearly separate the generic and "SoC"-specific code, thus allowing
>>> better maintenance.
>>>
>>> Does that makes sense to you guys?
>>
>> If you want to do that, then why not define your match data with your own
>> callbacks. e.g. something like
>>
>> struct sdhci_arasan_of_data {
>> struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
>> void (*platform_init)(struct sdhci_arasan_data *sdhci_arasan);
>> };
>>
>> struct sdhci_arasan_of_data *data;
>>
>> data = match->data;
>> sdhci_arasan->soc_ctl_map = data->soc_ctl_map;
>> if (data->platform_init)
>> platform_init(sdhci_arasan);
>
> Well, that adds a level in the hierarchy, but here is what it would look like:
>
>
> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
> index 410a55b..1cb3861 100644
> --- a/drivers/mmc/host/sdhci-of-arasan.c
> +++ b/drivers/mmc/host/sdhci-of-arasan.c
> @@ -382,22 +382,6 @@ static int sdhci_arasan_resume(struct device *dev)
> static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
> sdhci_arasan_resume);
>
> -static const struct of_device_id sdhci_arasan_of_match[] = {
> - /* SoC-specific compatible strings w/ soc_ctl_map */
> - {
> - .compatible = "rockchip,rk3399-sdhci-5.1",
> - .data = &rk3399_soc_ctl_map,
> - },
> -
> - /* Generic compatible below here */
> - { .compatible = "arasan,sdhci-8.9a" },
> - { .compatible = "arasan,sdhci-5.1" },
> - { .compatible = "arasan,sdhci-4.9a" },
> -
> - { /* sentinel */ }
> -};
> -MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
> -
> /**
> * sdhci_arasan_sdcardclk_recalc_rate - Return the card clock rate
> *
> @@ -578,6 +562,53 @@ static void sdhci_arasan_unregister_sdclk(struct device *dev)
> of_clk_del_provider(dev->of_node);
> }
>
> +static void sdhci_tango4_platform_init(struct sdhci_host *host)
> +{
> + printk("%s\n", __func__);
> +
> + /*
> + pad_mode[2:0]=0 must be 0
> + sel_sdio[3]=1 must be 1 for SDIO
> + inv_sdwp_pol[4]=0 if set inverts the SD write protect polarity
> + inv_sdcd_pol[5]=0 if set inverts the SD card present polarity
> + */
> + sdhci_writel(host, 0x00000008, 0x100 + 0x0);
> +}
> +
> +struct sdhci_arasan_chip_specific_data {
> + const struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
> + void (*platform_init)(struct sdhci_host *host);
> +};
> +
> +static const struct sdhci_arasan_chip_specific_data sdhci_arasan_rockchip = {
> + .soc_ctl_map = &rk3399_soc_ctl_map,
> +};
> +
> +static const struct sdhci_arasan_chip_specific_data sdhci_arasan_sigma = {
> + .platform_init = sdhci_tango4_platform_init,
> +};
> +
> +static const struct of_device_id sdhci_arasan_of_match[] = {
> + /* SoC-specific compatible strings w/ soc_ctl_map */
> + {
> + .compatible = "rockchip,rk3399-sdhci-5.1",
> + .data = &sdhci_arasan_rockchip,
> + },
> + {
> + .compatible = "sigma,sdio-v1",
> + .data = &sdhci_arasan_sigma,
> + },
> +
> + /* Generic compatible below here */
> + { .compatible = "arasan,sdhci-8.9a" },
> + { .compatible = "arasan,sdhci-5.1" },
> + { .compatible = "arasan,sdhci-4.9a" },
> +
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
> +
> +
> static int sdhci_arasan_probe(struct platform_device *pdev)
> {
> int ret;
> @@ -587,6 +618,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
> struct sdhci_host *host;
> struct sdhci_pltfm_host *pltfm_host;
> struct sdhci_arasan_data *sdhci_arasan;
> + struct sdhci_arasan_chip_specific_data *sdhci_arasan_chip_specific;
> struct device_node *np = pdev->dev.of_node;
>
> host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata,
> @@ -599,7 +631,11 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
> sdhci_arasan->host = host;
>
> match = of_match_node(sdhci_arasan_of_match, pdev->dev.of_node);
> - sdhci_arasan->soc_ctl_map = match->data;
> + sdhci_arasan_chip_specific = (struct sdhci_arasan_chip_specific_data *)match;
> + if (sdhci_arasan_chip_specific->soc_ctl_map)
> + sdhci_arasan->soc_ctl_map = sdhci_arasan_chip_specific->soc_ctl_map;
> + if (sdhci_arasan_chip_specific->platform_init)
> + sdhci_arasan_chip_specific->platform_init(host);
>
> node = of_parse_phandle(pdev->dev.of_node, "arasan,soc-ctl-syscon", 0);
> if (node) {
>
>
> I will try to send another patch with what a different approach
>
Here's a different approach (I just tested that it built, because I don't have the
rk3399 platform):
diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 410a55b..5be6e67 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -382,22 +382,6 @@ static int sdhci_arasan_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
sdhci_arasan_resume);
-static const struct of_device_id sdhci_arasan_of_match[] = {
- /* SoC-specific compatible strings w/ soc_ctl_map */
- {
- .compatible = "rockchip,rk3399-sdhci-5.1",
- .data = &rk3399_soc_ctl_map,
- },
-
- /* Generic compatible below here */
- { .compatible = "arasan,sdhci-8.9a" },
- { .compatible = "arasan,sdhci-5.1" },
- { .compatible = "arasan,sdhci-4.9a" },
-
- { /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
-
/**
* sdhci_arasan_sdcardclk_recalc_rate - Return the card clock rate
*
@@ -578,28 +562,18 @@ static void sdhci_arasan_unregister_sdclk(struct device *dev)
of_clk_del_provider(dev->of_node);
}
-static int sdhci_arasan_probe(struct platform_device *pdev)
+static int sdhci_rockchip_platform_init(struct sdhci_host *host,
+ struct platform_device *pdev)
{
int ret;
- const struct of_device_id *match;
struct device_node *node;
- struct clk *clk_xin;
- struct sdhci_host *host;
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_arasan_data *sdhci_arasan;
- struct device_node *np = pdev->dev.of_node;
-
- host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata,
- sizeof(*sdhci_arasan));
- if (IS_ERR(host))
- return PTR_ERR(host);
pltfm_host = sdhci_priv(host);
sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
- sdhci_arasan->host = host;
- match = of_match_node(sdhci_arasan_of_match, pdev->dev.of_node);
- sdhci_arasan->soc_ctl_map = match->data;
+ sdhci_arasan->soc_ctl_map = &rk3399_soc_ctl_map;
node = of_parse_phandle(pdev->dev.of_node, "arasan,soc-ctl-syscon", 0);
if (node) {
@@ -611,10 +585,107 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev, "Can't get syscon: %d\n",
ret);
- goto err_pltfm_free;
+ return -1;
}
}
+ if (of_property_read_bool(pdev->dev.of_node, "xlnx,fails-without-test-cd"))
+ sdhci_arasan->quirks |= SDHCI_ARASAN_QUIRK_FORCE_CDTEST;
+
+ return 0;
+}
+
+static int sdhci_rockchip_clock_init(struct sdhci_host *host,
+ struct platform_device *pdev)
+{
+ struct sdhci_pltfm_host *pltfm_host;
+ struct sdhci_arasan_data *sdhci_arasan;
+
+ pltfm_host = sdhci_priv(host);
+ sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+
+ if (of_device_is_compatible(pdev->dev.of_node,
+ "rockchip,rk3399-sdhci-5.1"))
+ sdhci_arasan_update_clockmultiplier(host, 0x0);
+
+ sdhci_arasan_update_baseclkfreq(host);
+
+ return sdhci_arasan_register_sdclk(sdhci_arasan, pltfm_host->clk, &pdev->dev);
+}
+
+static int sdhci_tango_platform_init(struct sdhci_host *host,
+ struct platform_device *pdev)
+{
+ return 0;
+}
+
+/* Chip-specific ops */
+struct sdhci_arasan_cs_ops {
+ int (*platform_init)(struct sdhci_host *host,
+ struct platform_device *pdev);
+ int (*clock_init)(struct sdhci_host *host,
+ struct platform_device *pdev);
+};
+
+static const struct sdhci_arasan_cs_ops sdhci_rockchip_cs_ops = {
+ .platform_init = sdhci_rockchip_platform_init,
+ .clock_init = sdhci_rockchip_clock_init,
+};
+
+static const struct sdhci_arasan_cs_ops sdhci_tango_cs_ops = {
+ .platform_init = sdhci_tango_platform_init,
+};
+
+static const struct of_device_id sdhci_arasan_of_match[] = {
+ /* SoC-specific compatible strings */
+ {
+ .compatible = "rockchip,rk3399-sdhci-5.1",
+ .data = &sdhci_rockchip_cs_ops,
+ },
+ {
+ .compatible = "sigma,sdio-v1",
+ .data = &sdhci_tango_cs_ops,
+ },
+
+ /* Generic compatible below here */
+ { .compatible = "arasan,sdhci-8.9a" },
+ { .compatible = "arasan,sdhci-5.1" },
+ { .compatible = "arasan,sdhci-4.9a" },
+
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
+
+static int sdhci_arasan_probe(struct platform_device *pdev)
+{
+ int ret;
+ const struct of_device_id *match;
+ struct clk *clk_xin;
+ struct sdhci_host *host;
+ struct sdhci_pltfm_host *pltfm_host;
+ struct sdhci_arasan_data *sdhci_arasan;
+ const struct sdhci_arasan_cs_ops *cs_ops;
+
+ host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata,
+ sizeof(*sdhci_arasan));
+ if (IS_ERR(host))
+ return PTR_ERR(host);
+
+ pltfm_host = sdhci_priv(host);
+ sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+ sdhci_arasan->host = host;
+
+ match = of_match_device(sdhci_arasan_of_match, &pdev->dev);
+ if (match)
+ cs_ops = match->data;
+
+ /* SoC-specific platform init */
+ if (cs_ops && cs_ops->platform_init) {
+ ret = cs_ops->platform_init(host, pdev);
+ if (ret)
+ goto err_pltfm_free;
+ }
+
sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb");
if (IS_ERR(sdhci_arasan->clk_ahb)) {
dev_err(&pdev->dev, "clk_ahb clock not found.\n");
@@ -642,21 +713,14 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
}
sdhci_get_of_property(pdev);
-
- if (of_property_read_bool(np, "xlnx,fails-without-test-cd"))
- sdhci_arasan->quirks |= SDHCI_ARASAN_QUIRK_FORCE_CDTEST;
-
pltfm_host->clk = clk_xin;
- if (of_device_is_compatible(pdev->dev.of_node,
- "rockchip,rk3399-sdhci-5.1"))
- sdhci_arasan_update_clockmultiplier(host, 0x0);
-
- sdhci_arasan_update_baseclkfreq(host);
-
- ret = sdhci_arasan_register_sdclk(sdhci_arasan, clk_xin, &pdev->dev);
- if (ret)
- goto clk_disable_all;
+ /* SoC-specific clock init */
+ if (cs_ops && cs_ops->clock_init) {
+ ret = cs_ops->clock_init(host, pdev);
+ if (ret)
+ goto clk_disable_all;
+ }
ret = mmc_of_parse(host->mmc);
if (ret) {
If you are ok with it I can clean it up to submit it properly.
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