[PATCH RESEND v2 1/2] mtd: rawnand: meson: discard the common MMC sub clock framework
Jerome Brunet
jbrunet at baylibre.com
Mon Feb 28 03:28:57 PST 2022
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 ?
> + 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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