[PATCH 04/11] fsmc/nand: Accept nand timing parameters via DT
Vipin Kumar
vipin.kumar at st.com
Thu Oct 11 00:25:31 EDT 2012
On 10/9/2012 5:27 PM, Jean-Christophe PLAGNIOL-VILLARD wrote:
> On 16:14 Tue 09 Oct , Vipin Kumar wrote:
>> Add support to accept nand timing parameters via device tree
>>
>> Signed-off-by: Vipin Kumar<vipin.kumar at st.com>
>> ---
>> .../devicetree/bindings/mtd/fsmc-nand.txt | 20 ++++++++
>> drivers/mtd/nand/fsmc_nand.c | 59 ++++++++++++++--------
>> include/linux/mtd/fsmc.h | 2 +-
>> 3 files changed, 59 insertions(+), 22 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
>> index 29d1a2f..6a7fc43 100644
>> --- a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
>> +++ b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
>> @@ -13,6 +13,18 @@ Optional properties:
>> defaults to 1 byte
>> - nand-skip-bbtscan: Indicates the the BBT scanning should be skipped
>>
>> +- nand-timings-enabled: Indicates if the timing parameters are passed
>> + via DT
>> +- nand-timings,tclr:
>> +- nand-timings,tar:
>> +- nand-timings,thiz:
>> +- nand-timings,thold:
>> +- nand-timings,twait:
>> +- nand-timings,tset: All these timing parameters come from the actual
>> + nand device specification. Each of this represents a number of time
>> + period of hclk ie a number 4 in thold with hclk = 166MHz means that
>> + thold = (1000 / 166) * 4 ns = 24.09ns
>> +
>> Example:
>>
>> fsmc: flash at d1800000 {
>> @@ -26,6 +38,14 @@ Example:
>> st,cle-off =<0x10000>;
>> maxbanks =<1>;
>>
>> + nand-timings-enabled;
>> + nand-timings,tclr =<1>;
>> + nand-timings,tar =<1>;
>> + nand-timings,thiz =<1>;
>> + nand-timings,thold =<4>;
>> + nand-timings,twait =<6>;
>> + nand-timings,tset =<0>;
>> +
>> bank-width =<1>;
>> nand-skip-bbtscan;
>>
>> diff --git a/drivers/mtd/nand/fsmc_nand.c b/drivers/mtd/nand/fsmc_nand.c
>> index fc6a044..f3d69b3 100644
>> --- a/drivers/mtd/nand/fsmc_nand.c
>> +++ b/drivers/mtd/nand/fsmc_nand.c
>> @@ -415,27 +415,13 @@ static void fsmc_nand_setup(void __iomem *regs, uint32_t bank,
>> {
>> uint32_t value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;
>> uint32_t tclr, tar, thiz, thold, twait, tset;
>> - struct fsmc_nand_timings *tims;
>> - struct fsmc_nand_timings default_timings = {
>> - .tclr = FSMC_TCLR_1,
>> - .tar = FSMC_TAR_1,
>> - .thiz = FSMC_THIZ_1,
>> - .thold = FSMC_THOLD_4,
>> - .twait = FSMC_TWAIT_6,
>> - .tset = FSMC_TSET_0,
>> - };
>> -
>> - if (timings)
>> - tims = timings;
>> - else
>> - tims =&default_timings;
>>
>> - tclr = (tims->tclr& FSMC_TCLR_MASK)<< FSMC_TCLR_SHIFT;
>> - tar = (tims->tar& FSMC_TAR_MASK)<< FSMC_TAR_SHIFT;
>> - thiz = (tims->thiz& FSMC_THIZ_MASK)<< FSMC_THIZ_SHIFT;
>> - thold = (tims->thold& FSMC_THOLD_MASK)<< FSMC_THOLD_SHIFT;
>> - twait = (tims->twait& FSMC_TWAIT_MASK)<< FSMC_TWAIT_SHIFT;
>> - tset = (tims->tset& FSMC_TSET_MASK)<< FSMC_TSET_SHIFT;
>> + tclr = (timings->tclr& FSMC_TCLR_MASK)<< FSMC_TCLR_SHIFT;
>> + tar = (timings->tar& FSMC_TAR_MASK)<< FSMC_TAR_SHIFT;
>> + thiz = (timings->thiz& FSMC_THIZ_MASK)<< FSMC_THIZ_SHIFT;
>> + thold = (timings->thold& FSMC_THOLD_MASK)<< FSMC_THOLD_SHIFT;
>> + twait = (timings->twait& FSMC_TWAIT_MASK)<< FSMC_TWAIT_SHIFT;
>> + tset = (timings->tset& FSMC_TSET_MASK)<< FSMC_TSET_SHIFT;
>>
>> if (busw)
>> writel(value | FSMC_DEVWID_16, FSMC_NAND_REG(regs, bank, PC));
>> @@ -876,6 +862,14 @@ static int __devinit fsmc_nand_probe_config_dt(struct platform_device *pdev,
>> struct device_node *np)
>> {
>> struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
>> + struct fsmc_nand_timings default_timings = {
>> + .tclr = FSMC_TCLR_1,
>> + .tar = FSMC_TAR_1,
>> + .thiz = FSMC_THIZ_1,
>> + .thold = FSMC_THOLD_4,
>> + .twait = FSMC_TWAIT_6,
>> + .tset = FSMC_TSET_0,
>> + };
>> u32 val;
>>
>> /* Set default NAND width to 8 bits */
>> @@ -894,6 +888,29 @@ static int __devinit fsmc_nand_probe_config_dt(struct platform_device *pdev,
>> pdata->options = NAND_SKIP_BBTSCAN;
>> of_property_read_u32(np, "maxbanks",&pdata->max_banks);
>>
>> + if (of_property_read_bool(np, "nand-timings-enabled")) {
>> + of_property_read_u32(np, "nand-timings,tclr",&val);
>> + pdata->nand_timings.tclr = (uint8_t)val;
> use a mask will be better
OK, will add a mask in v2
>> +
>> + of_property_read_u32(np, "nand-timings,tar",&val);
>> + pdata->nand_timings.tar = (uint8_t)val;
>> +
>> + of_property_read_u32(np, "nand-timings,thiz",&val);
>> + pdata->nand_timings.thiz = (uint8_t)val;
>> +
>> + of_property_read_u32(np, "nand-timings,thold",&val);
>> + pdata->nand_timings.thold = (uint8_t)val;
>> +
>> + of_property_read_u32(np, "nand-timings,twait",&val);
>> + pdata->nand_timings.twait = (uint8_t)val;
>> +
>> + of_property_read_u32(np, "nand-timings,tset",&val);
>> + pdata->nand_timings.tset = (uint8_t)val;
>> + } else {
>> + memcpy(&pdata->nand_timings,&default_timings,
>> + sizeof(default_timings));
>> + }
>> +
>> return 0;
>> }
>> #else
>> @@ -1031,7 +1048,7 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
>> host->partitions = pdata->partitions;
>> host->nr_partitions = pdata->nr_partitions;
>> host->dev =&pdev->dev;
>> - host->dev_timings = pdata->nand_timings;
>> + host->dev_timings =&pdata->nand_timings;
>> host->mode = pdata->mode;
>> host->max_banks = pdata->max_banks;
>>
>> diff --git a/include/linux/mtd/fsmc.h b/include/linux/mtd/fsmc.h
>> index f0ab734..4fbdce4 100644
>> --- a/include/linux/mtd/fsmc.h
>> +++ b/include/linux/mtd/fsmc.h
>> @@ -148,7 +148,7 @@ enum access_mode {
>> * this may be set to NULL
>> */
>> struct fsmc_nand_platform_data {
>> - struct fsmc_nand_timings *nand_timings;
>> + struct fsmc_nand_timings nand_timings;
>> struct mtd_partition *partitions;
>> unsigned int nr_partitions;
>> unsigned int options;
>> --
>> 1.7.11.4
>>
> .
>
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