[PATCH RESEND v2 1/2] mtd: rawnand: meson: discard the common MMC sub clock framework
Liang Yang
liang.yang at amlogic.com
Fri Mar 11 00:28:32 PST 2022
Hello Jerome,
On 2022/2/28 19:28, Jerome Brunet wrote:
> [ EXTERNAL EMAIL ]
>
>
> On Thu 17 Feb 2022 at 14:33, Liang Yang <liang.yang at amlogic.com> wrote:
>
>> 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 | 107 +++++++++++++++++-------------
>> 1 file changed, 61 insertions(+), 46 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
>> index ac3be92872d0..c5b892d38ea0 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;
>> @@ -988,6 +993,8 @@ static const struct mtd_ooblayout_ops meson_ooblayout_ops = {
>> static int meson_nfc_clk_init(struct meson_nfc *nfc)
>> {
>> int ret;
>> + struct clk_init_data init = {0};
>> + struct clk_parent_data nfc_divider_parent_data[1];
>>
>> /* request core clock */
>> nfc->core_clk = devm_clk_get(nfc->dev, "core");
>> @@ -1002,21 +1009,26 @@ 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 = __clk_get_name(nfc->device_clk);
>
> This is broken.
> __clk_get_name() gives the actual global name of the clock
> "fw_name" is the DT name which allows to find the index on the clock
>
>>From the DT doc, the fw_name is either 'core' or 'device'
>
> I don't think any clock would have such a name so I don't think this can
> actually work. Did you actually test this ?
> Indeed, it can't work. i have tried it.
so let us get solved by nfc_divider_parent_data[0].fw_name = "device" or
previous parent_names? thanks.
>
>> + 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 +1042,21 @@ static int meson_nfc_clk_init(struct meson_nfc *nfc)
>> goto err_device_clk;
>> }
>>
>> - ret = clk_prepare_enable(nfc->phase_tx);
>> - if (ret) {
>> - dev_err(nfc->dev, "failed to enable TX clock\n");
>> - goto err_phase_tx;
>> - }
>> -
>> - ret = clk_prepare_enable(nfc->phase_rx);
>> + ret = clk_prepare_enable(nfc->nand_clk);
>> if (ret) {
>> - dev_err(nfc->dev, "failed to enable RX clock\n");
>> - goto err_phase_rx;
>> + dev_err(nfc->dev, "pre enable NFC divider fail\n");
>> + goto err_nand_clk;
>> }
>>
>> ret = clk_set_rate(nfc->device_clk, 24000000);
>> 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 +1065,7 @@ 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);
>> }
>> @@ -1370,11 +1373,31 @@ static const struct of_device_id meson_nfc_id_table[] = {
>> };
>> MODULE_DEVICE_TABLE(of, meson_nfc_id_table);
>>
>> +static int meson_nfc_reg_resource(struct device *dev, struct meson_nfc *nfc)
>> +{
>> + struct resource res;
>> + void __iomem *base[2];
>> + struct device_node *node = dev->of_node;
>> + int i;
>> +
>> + for (i = 0; i < 2; i++) {
>> + if (of_address_to_resource(node, i, &res))
>> + return -ENOENT;
>> +
>> + base[i] = devm_ioremap_resource(dev, &res);
>> + if (IS_ERR(base))
>> + return PTR_ERR(base);
>> + }
>> + nfc->reg_base = base[0];
>> + nfc->sd_emmc_clock = base[1];
>> +
>
> There is no reason to make a separate function for this.
>
> Please name your ressource and claim them properly instead of interating
> on them.
>
>
>> + return 0;
>> +}
>> +
>> 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);
>> @@ -1388,20 +1411,12 @@ static int meson_nfc_probe(struct platform_device *pdev)
>> nand_controller_init(&nfc->controller);
>> INIT_LIST_HEAD(&nfc->chips);
>> init_completion(&nfc->completion);
>> -
>> nfc->dev = dev;
>>
>> - res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> - nfc->reg_base = devm_ioremap_resource(dev, res);
>> - 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);
>> + ret = meson_nfc_reg_resource(dev, nfc);
>> + if (ret) {
>> + dev_err(dev, "Failed to get reg resource\n");
>> + return ret;
>> }
>>
>> irq = platform_get_irq(pdev, 0);
>
> .
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