Re: [PATCH v3 2/3] dmaengine: dw-axi-dmac: Add support for StarFive JH7110 DMA

From: Walker Chen
Date: Fri Mar 03 2023 - 03:18:34 EST



On 2023/2/27 21:47, Emil Renner Berthing wrote:
> On Mon, 27 Feb 2023 at 14:11, Walker Chen <walker.chen@xxxxxxxxxxxxxxxx> wrote:
>>
>> Add DMA reset operation in device probe and use different configuration
>> on CH_CFG registers according to match data.
>>
>> Signed-off-by: Walker Chen <walker.chen@xxxxxxxxxxxxxxxx>
>> Reviewed-by: Emil Renner Berthing <emil.renner.berthing@xxxxxxxxxxxxx>
>
> Hi Walker,
>
> Firstly your Signed-off-by should be the last line.
>
> I may have been unclear in my last review, sorry. I meant to give my
> reviewed-by if you just removed the reset pointer that was never used.
> This new version also adds a lot of new code.
>
> Though, I'm glad you want to update the driver to use match data
> rather than of_device_is_compatible, but then please update all uses
> of of_device_is_compatible. With this patch starfive uses match data
> and the intel,kmb-axi-dma still uses of_device_is_compatible.

Hey Emil, thank you for pointing out these problems for me.
Will be fixed.

> More comments below..
>
>> ---
>> .../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 34 +++++++++++++++++--
>> drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 7 ++++
>> 2 files changed, 39 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
>> index bf85aa0979ec..400eeef707bf 100644
>> --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
>> +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
>> @@ -21,10 +21,12 @@
>> #include <linux/kernel.h>
>> #include <linux/module.h>
>> #include <linux/of.h>
>> +#include <linux/of_device.h>
>> #include <linux/of_dma.h>
>> #include <linux/platform_device.h>
>> #include <linux/pm_runtime.h>
>> #include <linux/property.h>
>> +#include <linux/reset.h>
>> #include <linux/slab.h>
>> #include <linux/types.h>
>>
>> @@ -86,7 +88,8 @@ static inline void axi_chan_config_write(struct axi_dma_chan *chan,
>>
>> cfg_lo = (config->dst_multblk_type << CH_CFG_L_DST_MULTBLK_TYPE_POS |
>> config->src_multblk_type << CH_CFG_L_SRC_MULTBLK_TYPE_POS);
>> - if (chan->chip->dw->hdata->reg_map_8_channels) {
>> + if (chan->chip->dw->hdata->reg_map_8_channels &&
>> + !chan->chip->dw->hdata->use_cfg2) {
>> cfg_hi = config->tt_fc << CH_CFG_H_TT_FC_POS |
>> config->hs_sel_src << CH_CFG_H_HS_SEL_SRC_POS |
>> config->hs_sel_dst << CH_CFG_H_HS_SEL_DST_POS |
>> @@ -1142,7 +1145,7 @@ static int dma_chan_terminate_all(struct dma_chan *dchan)
>> axi_chan_disable(chan);
>>
>> ret = readl_poll_timeout_atomic(chan->chip->regs + DMAC_CHEN, val,
>> - !(val & chan_active), 1000, 10000);
>> + !(val & chan_active), 1000, DMAC_TIMEOUT_US);
>> if (ret == -ETIMEDOUT)
>> dev_warn(dchan2dev(dchan),
>> "%s failed to stop\n", axi_chan_name(chan));
>> @@ -1367,6 +1370,17 @@ static int parse_device_properties(struct axi_dma_chip *chip)
>> return 0;
>> }
>>
>> +static int jh7110_rst_init(struct platform_device *pdev)
>> +{
>> + struct reset_control *resets;
>> +
>> + resets = devm_reset_control_array_get_exclusive(&pdev->dev);
>> + if (IS_ERR(resets))
>> + return PTR_ERR(resets);
>> +
>> + return reset_control_deassert(resets);
>> +}
>> +
>> static int dw_probe(struct platform_device *pdev)
>> {
>> struct device_node *node = pdev->dev.of_node;
>> @@ -1374,6 +1388,7 @@ static int dw_probe(struct platform_device *pdev)
>> struct resource *mem;
>> struct dw_axi_dma *dw;
>> struct dw_axi_dma_hcfg *hdata;
>> + const struct axi_dma_chip_config *ccfg;
>> u32 i;
>> int ret;
>>
>> @@ -1416,6 +1431,15 @@ static int dw_probe(struct platform_device *pdev)
>> if (IS_ERR(chip->cfgr_clk))
>> return PTR_ERR(chip->cfgr_clk);
>>
>> + ccfg = of_device_get_match_data(&pdev->dev);
>> + if (ccfg) {
>> + ret = ccfg->rst_init(pdev);
>> + if (ret)
>> + return ret;
>> +
>> + chip->dw->hdata->use_cfg2 = ccfg->use_cfg2;
>> + }
>> +
>> ret = parse_device_properties(chip);
>> if (ret)
>> return ret;
>> @@ -1557,9 +1581,15 @@ static const struct dev_pm_ops dw_axi_dma_pm_ops = {
>> SET_RUNTIME_PM_OPS(axi_dma_runtime_suspend, axi_dma_runtime_resume, NULL)
>> };
>>
>> +static const struct axi_dma_chip_config jh7110_chip_config = {
>> + .rst_init = jh7110_rst_init,
>> + .use_cfg2 = true,
>> +};
>> +
>> static const struct of_device_id dw_dma_of_id_table[] = {
>> { .compatible = "snps,axi-dma-1.01a" },
>> { .compatible = "intel,kmb-axi-dma" },
>> + { .compatible = "starfive,jh7110-axi-dma", .data = &jh7110_chip_config },
>> {}
>> };
>> MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
>> diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
>> index e9d5eb0fd594..7b404ae9a26a 100644
>> --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
>> +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
>> @@ -21,6 +21,7 @@
>> #define DMAC_MAX_CHANNELS 16
>> #define DMAC_MAX_MASTERS 2
>> #define DMAC_MAX_BLK_SIZE 0x200000
>> +#define DMAC_TIMEOUT_US 200000
>>
>> struct dw_axi_dma_hcfg {
>> u32 nr_channels;
>> @@ -33,6 +34,7 @@ struct dw_axi_dma_hcfg {
>> /* Register map for DMAX_NUM_CHANNELS <= 8 */
>> bool reg_map_8_channels;
>> bool restrict_axi_burst_len;
>> + bool use_cfg2;
>> };
>>
>> struct axi_dma_chan {
>> @@ -72,6 +74,11 @@ struct axi_dma_chip {
>> struct dw_axi_dma *dw;
>> };
>>
>> +struct axi_dma_chip_config {
>> + int (*rst_init)(struct platform_device *pdev);
>
> Please just spell reset in full, it's not that much longer.

Okay, this will be modified.

>
>> + bool use_cfg2;
>> +};
>> +
>
> This struct is only used in dw-axi-dmac-platform.c above, so no need
> to add it here.

Okay, will be fixed.

Thank you very much for your review and comment!

Best regards,
Walker