[PATCH v4 1/2] mtd: rawnand: meson: discard the common MMC sub clock framework
Liang Yang
liang.yang at amlogic.com
Sun Apr 10 19:40:15 PDT 2022
Hi Miquel,
On 2022/4/4 16:30, Miquel Raynal wrote:
> [ EXTERNAL EMAIL ]
>
> Hi Liang,
>
> liang.yang at amlogic.com wrote on Sat, 2 Apr 2022 15:49:19 +0800:
>
>> EMMC and NAND have the same clock control register named 'SD_EMMC_CLOCK' which is
>> defined in EMMC port internally. bit0~5 of 'SD_EMMC_CLOCK' is the divider and
>> bit6~7 is the mux for fix pll and xtal.A common MMC and NAND sub-clock has been
>> implemented and can be used by the eMMC and NAND controller (which are mutually
>> exclusive anyway). Let's use this new clock.
>>
>> Signed-off-by: Liang Yang <liang.yang at amlogic.com>
>> ---
>> drivers/mtd/nand/raw/meson_nand.c | 89 +++++++++++++++----------------
>> 1 file changed, 42 insertions(+), 47 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
>> index ac3be92872d0..1b1a9407fb2f 100644
>> --- a/drivers/mtd/nand/raw/meson_nand.c
>> +++ b/drivers/mtd/nand/raw/meson_nand.c
>> @@ -10,6 +10,7 @@
>> #include <linux/dma-mapping.h>
>> #include <linux/interrupt.h>
>> #include <linux/clk.h>
>> +#include <linux/clk-provider.h>
>> #include <linux/mtd/rawnand.h>
>> #include <linux/mtd/mtd.h>
>> #include <linux/mfd/syscon.h>
>> @@ -19,6 +20,7 @@
>> #include <linux/iopoll.h>
>> #include <linux/of.h>
>> #include <linux/of_device.h>
>> +#include <linux/of_address.h>
>> #include <linux/sched/task_stack.h>
>>
>> #define NFC_REG_CMD 0x00
>> @@ -104,6 +106,9 @@
>>
>> #define PER_INFO_BYTE 8
>>
>> +#define CLK_DIV_SHIFT 0
>> +#define CLK_DIV_WIDTH 6
>> +
>> struct meson_nfc_nand_chip {
>> struct list_head node;
>> struct nand_chip nand;
>> @@ -151,15 +156,15 @@ struct meson_nfc {
>> struct nand_controller controller;
>> struct clk *core_clk;
>> struct clk *device_clk;
>> - struct clk *phase_tx;
>> - struct clk *phase_rx;
>> + struct clk *nand_clk;
>> + struct clk_divider nand_divider;
>>
>> unsigned long clk_rate;
>> u32 bus_timing;
>>
>> struct device *dev;
>> void __iomem *reg_base;
>> - struct regmap *reg_clk;
>> + void __iomem *sd_emmc_clock;
>> struct completion completion;
>> struct list_head chips;
>> const struct meson_nfc_data *data;
>> @@ -235,7 +240,7 @@ static void meson_nfc_select_chip(struct nand_chip *nand, int chip)
>> nfc->timing.tbers_max = meson_chip->tbers_max;
>>
>> if (nfc->clk_rate != meson_chip->clk_rate) {
>> - ret = clk_set_rate(nfc->device_clk, meson_chip->clk_rate);
>> + ret = clk_set_rate(nfc->nand_clk, meson_chip->clk_rate);
>> if (ret) {
>> dev_err(nfc->dev, "failed to set clock rate\n");
>> return;
>> @@ -406,7 +411,6 @@ static int meson_nfc_queue_rb(struct meson_nfc *nfc, int timeout_ms)
>> cmd = NFC_CMD_RB | NFC_CMD_RB_INT
>> | nfc->param.chip_select | nfc->timing.tbers_max;
>> writel(cmd, nfc->reg_base + NFC_REG_CMD);
>> -
>
> Please avoid these spacing changes in the middle of a commit.
ok, i will fix it.
>
>> ret = wait_for_completion_timeout(&nfc->completion,
>> msecs_to_jiffies(timeout_ms));
>> if (ret == 0)
>> @@ -985,9 +989,11 @@ static const struct mtd_ooblayout_ops meson_ooblayout_ops = {
>> .free = meson_ooblayout_free,
>> };
>>
>> +struct clk_parent_data nfc_divider_parent_data[1];
>> static int meson_nfc_clk_init(struct meson_nfc *nfc)
>> {
>> int ret;
>> + struct clk_init_data init = {0};
>>
>> /* request core clock */
>> nfc->core_clk = devm_clk_get(nfc->dev, "core");
>> @@ -1002,21 +1008,26 @@ static int meson_nfc_clk_init(struct meson_nfc *nfc)
>> return PTR_ERR(nfc->device_clk);
>> }
>>
>> - nfc->phase_tx = devm_clk_get(nfc->dev, "tx");
>> - if (IS_ERR(nfc->phase_tx)) {
>> - dev_err(nfc->dev, "failed to get TX clk\n");
>> - return PTR_ERR(nfc->phase_tx);
>> - }
>> -
>> - nfc->phase_rx = devm_clk_get(nfc->dev, "rx");
>> - if (IS_ERR(nfc->phase_rx)) {
>> - dev_err(nfc->dev, "failed to get RX clk\n");
>> - return PTR_ERR(nfc->phase_rx);
>> - }
>> + init.name = devm_kstrdup(nfc->dev, "nfc#div", GFP_KERNEL);
>> + init.ops = &clk_divider_ops;
>> + nfc_divider_parent_data[0].fw_name = "device";
>> + init.parent_data = nfc_divider_parent_data;
>> + init.num_parents = 1;
>> + nfc->nand_divider.reg = nfc->sd_emmc_clock;
>> + nfc->nand_divider.shift = CLK_DIV_SHIFT;
>> + nfc->nand_divider.width = CLK_DIV_WIDTH;
>> + nfc->nand_divider.hw.init = &init;
>> + nfc->nand_divider.flags = CLK_DIVIDER_ONE_BASED |
>> + CLK_DIVIDER_ROUND_CLOSEST |
>> + CLK_DIVIDER_ALLOW_ZERO;
>> +
>> + nfc->nand_clk = devm_clk_register(nfc->dev, &nfc->nand_divider.hw);
>> + if (IS_ERR(nfc->nand_clk))
>> + return PTR_ERR(nfc->nand_clk);
>>
>> /* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
>> - regmap_update_bits(nfc->reg_clk,
>> - 0, CLK_SELECT_NAND, CLK_SELECT_NAND);
>> + writel(CLK_SELECT_NAND | readl(nfc->sd_emmc_clock),
>> + nfc->sd_emmc_clock);
>>
>> ret = clk_prepare_enable(nfc->core_clk);
>> if (ret) {
>> @@ -1030,29 +1041,21 @@ static int meson_nfc_clk_init(struct meson_nfc *nfc)
>> goto err_device_clk;
>> }
>>
>> - ret = clk_prepare_enable(nfc->phase_tx);
>> + ret = clk_prepare_enable(nfc->nand_clk);
>> if (ret) {
>> - dev_err(nfc->dev, "failed to enable TX clock\n");
>> - goto err_phase_tx;
>> + dev_err(nfc->dev, "pre enable NFC divider fail\n");
>> + goto err_nand_clk;
>> }
>>
>> - ret = clk_prepare_enable(nfc->phase_rx);
>> - if (ret) {
>> - dev_err(nfc->dev, "failed to enable RX clock\n");
>> - goto err_phase_rx;
>> - }
>> -
>> - ret = clk_set_rate(nfc->device_clk, 24000000);
>> + ret = clk_set_rate(nfc->nand_clk, 24000000);
>
> Is this rename really useful?
yes, it works.
>
>> if (ret)
>> - goto err_disable_rx;
>> + goto err_disable_clk;
>>
>> return 0;
>>
>> -err_disable_rx:
>> - clk_disable_unprepare(nfc->phase_rx);
>> -err_phase_rx:
>> - clk_disable_unprepare(nfc->phase_tx);
>> -err_phase_tx:
>> +err_disable_clk:
>> + clk_disable_unprepare(nfc->nand_clk);
>> +err_nand_clk:
>> clk_disable_unprepare(nfc->device_clk);
>> err_device_clk:
>> clk_disable_unprepare(nfc->core_clk);
>> @@ -1061,8 +1064,7 @@ static int meson_nfc_clk_init(struct meson_nfc *nfc)
>>
>> static void meson_nfc_disable_clk(struct meson_nfc *nfc)
>> {
>> - clk_disable_unprepare(nfc->phase_rx);
>> - clk_disable_unprepare(nfc->phase_tx);
>> + clk_disable_unprepare(nfc->nand_clk);
>> clk_disable_unprepare(nfc->device_clk);
>> clk_disable_unprepare(nfc->core_clk);
>> }
>> @@ -1374,7 +1376,6 @@ static int meson_nfc_probe(struct platform_device *pdev)
>> {
>> struct device *dev = &pdev->dev;
>> struct meson_nfc *nfc;
>> - struct resource *res;
>> int ret, irq;
>>
>> nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
>> @@ -1388,21 +1389,15 @@ static int meson_nfc_probe(struct platform_device *pdev)
>> nand_controller_init(&nfc->controller);
>> INIT_LIST_HEAD(&nfc->chips);
>> init_completion(&nfc->completion);
>> -
>
> Please don't modify spacing in this commit.
>ok
>> nfc->dev = dev;
>>
>> - res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> - nfc->reg_base = devm_ioremap_resource(dev, res);
>> + nfc->reg_base = devm_platform_ioremap_resource_byname(pdev, "nfc");
>
> This change seems unrelated.
To be consistent with the following
devm_platform_ioremap_resource_byname(pdev, "emmc"). do you mean that we
don't need it?>
>> if (IS_ERR(nfc->reg_base))
>> return PTR_ERR(nfc->reg_base);
>>
>> - nfc->reg_clk =
>> - syscon_regmap_lookup_by_phandle(dev->of_node,
>> - "amlogic,mmc-syscon");
>> - if (IS_ERR(nfc->reg_clk)) {
>> - dev_err(dev, "Failed to lookup clock base\n");
>> - return PTR_ERR(nfc->reg_clk);
>> - }
>> + nfc->sd_emmc_clock = devm_platform_ioremap_resource_byname(pdev, "emmc");
>> + if (IS_ERR(nfc->sd_emmc_clock))
>> + return PTR_ERR(nfc->sd_emmc_clock);
>
> While I agree this is much better than the previous solution, we cannot
> break DT compatibility, so you need to try getting the emmc clock, but
> if it fails you should fallback to the regmap lookup.
ok, i will fix it next version. thanks.
>
>>
>> irq = platform_get_irq(pdev, 0);
>> if (irq < 0)
>
>
> Thanks,
> Miquèl
>
> .
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