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Thu, 23 Jan 2025 08:15:32 -0800 (PST) Message-ID: <04d08bf8-d5a2-4262-8210-b5173b8c613b@linaro.org> Date: Thu, 23 Jan 2025 17:15:31 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Neil Armstrong Reply-To: neil.armstrong@linaro.org Subject: Re: [PATCH] soc: amlogic: clk-measure: Optimize the memory size of clk-measure To: chuan.liu@amlogic.com, Kevin Hilman , Jerome Brunet , Martin Blumenstingl Cc: linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org References: <20250123-optimize_memory_size_of_clk_measure-v1-1-06aa6a01ff37@amlogic.com> Content-Language: en-US, fr Autocrypt: addr=neil.armstrong@linaro.org; keydata= xsBNBE1ZBs8BCAD78xVLsXPwV/2qQx2FaO/7mhWL0Qodw8UcQJnkrWmgTFRobtTWxuRx8WWP GTjuhvbleoQ5Cxjr+v+1ARGCH46MxFP5DwauzPekwJUD5QKZlaw/bURTLmS2id5wWi3lqVH4 BVF2WzvGyyeV1o4RTCYDnZ9VLLylJ9bneEaIs/7cjCEbipGGFlfIML3sfqnIvMAxIMZrvcl9 qPV2k+KQ7q+aXavU5W+yLNn7QtXUB530Zlk/d2ETgzQ5FLYYnUDAaRl+8JUTjc0CNOTpCeik 80TZcE6f8M76Xa6yU8VcNko94Ck7iB4vj70q76P/J7kt98hklrr85/3NU3oti3nrIHmHABEB AAHNKk5laWwgQXJtc3Ryb25nIDxuZWlsLmFybXN0cm9uZ0BsaW5hcm8ub3JnPsLAkQQTAQoA OwIbIwULCQgHAwUVCgkICwUWAgMBAAIeAQIXgBYhBInsPQWERiF0UPIoSBaat7Gkz/iuBQJk Q5wSAhkBAAoJEBaat7Gkz/iuyhMIANiD94qDtUTJRfEW6GwXmtKWwl/mvqQtaTtZID2dos04 YqBbshiJbejgVJjy+HODcNUIKBB3PSLaln4ltdsV73SBcwUNdzebfKspAQunCM22Mn6FBIxQ GizsMLcP/0FX4en9NaKGfK6ZdKK6kN1GR9YffMJd2P08EO8mHowmSRe/ExAODhAs9W7XXExw UNCY4pVJyRPpEhv373vvff60bHxc1k/FF9WaPscMt7hlkbFLUs85kHtQAmr8pV5Hy9ezsSRa GzJmiVclkPc2BY592IGBXRDQ38urXeM4nfhhvqA50b/nAEXc6FzqgXqDkEIwR66/Gbp0t3+r yQzpKRyQif3OwE0ETVkGzwEIALyKDN/OGURaHBVzwjgYq+ZtifvekdrSNl8TIDH8g1xicBYp QTbPn6bbSZbdvfeQPNCcD4/EhXZuhQXMcoJsQQQnO4vwVULmPGgtGf8PVc7dxKOeta+qUh6+ SRh3vIcAUFHDT3f/Zdspz+e2E0hPV2hiSvICLk11qO6cyJE13zeNFoeY3ggrKY+IzbFomIZY 4yG6xI99NIPEVE9lNBXBKIlewIyVlkOaYvJWSV+p5gdJXOvScNN1epm5YHmf9aE2ZjnqZGoM Mtsyw18YoX9BqMFInxqYQQ3j/HpVgTSvmo5ea5qQDDUaCsaTf8UeDcwYOtgI8iL4oHcsGtUX oUk33HEAEQEAAcLAXwQYAQIACQUCTVkGzwIbDAAKCRAWmrexpM/4rrXiB/sGbkQ6itMrAIfn M7IbRuiSZS1unlySUVYu3SD6YBYnNi3G5EpbwfBNuT3H8//rVvtOFK4OD8cRYkxXRQmTvqa3 3eDIHu/zr1HMKErm+2SD6PO9umRef8V82o2oaCLvf4WeIssFjwB0b6a12opuRP7yo3E3gTCS KmbUuLv1CtxKQF+fUV1cVaTPMyT25Od+RC1K+iOR0F54oUJvJeq7fUzbn/KdlhA8XPGzwGRy 4zcsPWvwnXgfe5tk680fEKZVwOZKIEuJC3v+/yZpQzDvGYJvbyix0lHnrCzq43WefRHI5XTT QbM0WUIBIcGmq38+OgUsMYu4NzLu7uZFAcmp6h8g Organization: Linaro In-Reply-To: <20250123-optimize_memory_size_of_clk_measure-v1-1-06aa6a01ff37@amlogic.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi, On 23/01/2025 11:37, Chuan Liu via B4 Relay wrote: > From: Chuan Liu > > Define struct meson_msr as a static global variable and remove the > "*priv" member from struct meson_msr_id. > > Define the size of the corresponding array based on the actual number of > msr_id of the chip. > > The array corresponding to msr_id is defined as "__initdata" to reduce > memory usage. > > Signed-off-by: Chuan Liu > --- > Each msr_id defines a pointer(*priv), and all these pointers point to > the same address. > > The number of msr_ids for each chip is inconsistent. Defining a > fixed-size array for each chip to store msr_ids would waste memory. > --- > drivers/soc/amlogic/meson-clk-measure.c | 119 ++++++++++++++++++++------------ > 1 file changed, 74 insertions(+), 45 deletions(-) > > diff --git a/drivers/soc/amlogic/meson-clk-measure.c b/drivers/soc/amlogic/meson-clk-measure.c > index a6453ffeb753..b52e9ce25ea8 100644 > --- a/drivers/soc/amlogic/meson-clk-measure.c > +++ b/drivers/soc/amlogic/meson-clk-measure.c > @@ -33,23 +33,27 @@ static DEFINE_MUTEX(measure_lock); > #define DIV_STEP 32 > #define DIV_MAX 640 > > -#define CLK_MSR_MAX 128 > - > struct meson_msr_id { > - struct meson_msr *priv; > unsigned int id; > const char *name; > }; > > +struct meson_msr_data { > + struct meson_msr_id *msr_table; > + unsigned int msr_count; > +}; > + > struct meson_msr { > struct regmap *regmap; > - struct meson_msr_id msr_table[CLK_MSR_MAX]; > + struct meson_msr_data data; > }; > > #define CLK_MSR_ID(__id, __name) \ > [__id] = {.id = __id, .name = __name,} > > -static struct meson_msr_id clk_msr_m8[CLK_MSR_MAX] = { > +static struct meson_msr meson_msr; The whole architecture was to avoid a global variable like this > + > +static struct meson_msr_id clk_msr_m8[] __initdata = { > CLK_MSR_ID(0, "ring_osc_out_ee0"), > CLK_MSR_ID(1, "ring_osc_out_ee1"), > CLK_MSR_ID(2, "ring_osc_out_ee2"), > @@ -98,7 +102,7 @@ static struct meson_msr_id clk_msr_m8[CLK_MSR_MAX] = { > CLK_MSR_ID(63, "mipi_csi_cfg"), > }; > > -static struct meson_msr_id clk_msr_gx[CLK_MSR_MAX] = { > +static struct meson_msr_id clk_msr_gx[] __initdata = { > CLK_MSR_ID(0, "ring_osc_out_ee_0"), > CLK_MSR_ID(1, "ring_osc_out_ee_1"), > CLK_MSR_ID(2, "ring_osc_out_ee_2"), > @@ -168,7 +172,7 @@ static struct meson_msr_id clk_msr_gx[CLK_MSR_MAX] = { > CLK_MSR_ID(82, "ge2d"), > }; > > -static struct meson_msr_id clk_msr_axg[CLK_MSR_MAX] = { > +static struct meson_msr_id clk_msr_axg[] __initdata = { > CLK_MSR_ID(0, "ring_osc_out_ee_0"), > CLK_MSR_ID(1, "ring_osc_out_ee_1"), > CLK_MSR_ID(2, "ring_osc_out_ee_2"), > @@ -242,7 +246,7 @@ static struct meson_msr_id clk_msr_axg[CLK_MSR_MAX] = { > CLK_MSR_ID(109, "audio_locker_in"), > }; > > -static struct meson_msr_id clk_msr_g12a[CLK_MSR_MAX] = { > +static struct meson_msr_id clk_msr_g12a[] __initdata = { > CLK_MSR_ID(0, "ring_osc_out_ee_0"), > CLK_MSR_ID(1, "ring_osc_out_ee_1"), > CLK_MSR_ID(2, "ring_osc_out_ee_2"), > @@ -358,7 +362,7 @@ static struct meson_msr_id clk_msr_g12a[CLK_MSR_MAX] = { > CLK_MSR_ID(122, "audio_pdm_dclk"), > }; > > -static struct meson_msr_id clk_msr_sm1[CLK_MSR_MAX] = { > +static struct meson_msr_id clk_msr_sm1[] __initdata = { > CLK_MSR_ID(0, "ring_osc_out_ee_0"), > CLK_MSR_ID(1, "ring_osc_out_ee_1"), > CLK_MSR_ID(2, "ring_osc_out_ee_2"), > @@ -489,9 +493,8 @@ static struct meson_msr_id clk_msr_sm1[CLK_MSR_MAX] = { > }; > > static int meson_measure_id(struct meson_msr_id *clk_msr_id, > - unsigned int duration) > + unsigned int duration) > { > - struct meson_msr *priv = clk_msr_id->priv; > unsigned int val; > int ret; > > @@ -499,22 +502,22 @@ static int meson_measure_id(struct meson_msr_id *clk_msr_id, > if (ret) > return ret; > > - regmap_write(priv->regmap, MSR_CLK_REG0, 0); > + regmap_write(meson_msr.regmap, MSR_CLK_REG0, 0); > > /* Set measurement duration */ > - regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_DURATION, > + regmap_update_bits(meson_msr.regmap, MSR_CLK_REG0, MSR_DURATION, > FIELD_PREP(MSR_DURATION, duration - 1)); > > /* Set ID */ > - regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_CLK_SRC, > + regmap_update_bits(meson_msr.regmap, MSR_CLK_REG0, MSR_CLK_SRC, > FIELD_PREP(MSR_CLK_SRC, clk_msr_id->id)); > > /* Enable & Start */ > - regmap_update_bits(priv->regmap, MSR_CLK_REG0, > + regmap_update_bits(meson_msr.regmap, MSR_CLK_REG0, > MSR_RUN | MSR_ENABLE, > MSR_RUN | MSR_ENABLE); > > - ret = regmap_read_poll_timeout(priv->regmap, MSR_CLK_REG0, > + ret = regmap_read_poll_timeout(meson_msr.regmap, MSR_CLK_REG0, > val, !(val & MSR_BUSY), 10, 10000); > if (ret) { > mutex_unlock(&measure_lock); > @@ -522,10 +525,10 @@ static int meson_measure_id(struct meson_msr_id *clk_msr_id, > } > > /* Disable */ > - regmap_update_bits(priv->regmap, MSR_CLK_REG0, MSR_ENABLE, 0); > + regmap_update_bits(meson_msr.regmap, MSR_CLK_REG0, MSR_ENABLE, 0); > > /* Get the value in multiple of gate time counts */ > - regmap_read(priv->regmap, MSR_CLK_REG2, &val); > + regmap_read(meson_msr.regmap, MSR_CLK_REG2, &val); > > mutex_unlock(&measure_lock); > > @@ -579,7 +582,7 @@ static int clk_msr_summary_show(struct seq_file *s, void *data) > seq_puts(s, " clock rate precision\n"); > seq_puts(s, "---------------------------------------------\n"); > > - for (i = 0 ; i < CLK_MSR_MAX ; ++i) { > + for (i = 0 ; i < meson_msr.data.msr_count ; ++i) { > if (!msr_table[i].name) > continue; > > @@ -604,77 +607,103 @@ static const struct regmap_config meson_clk_msr_regmap_config = { > > static int meson_msr_probe(struct platform_device *pdev) > { > - const struct meson_msr_id *match_data; > - struct meson_msr *priv; > + const struct meson_msr_data *match_data; > + struct meson_msr_id *msr_table; > struct dentry *root, *clks; > void __iomem *base; > int i; > > - priv = devm_kzalloc(&pdev->dev, sizeof(struct meson_msr), > - GFP_KERNEL); > - if (!priv) > - return -ENOMEM; > - > match_data = device_get_match_data(&pdev->dev); > if (!match_data) { > dev_err(&pdev->dev, "failed to get match data\n"); > return -ENODEV; > } > > - memcpy(priv->msr_table, match_data, sizeof(priv->msr_table)); > + msr_table = devm_kcalloc(&pdev->dev, match_data->msr_count, > + sizeof(struct meson_msr_id), GFP_KERNEL); > + if (!msr_table) > + return -ENOMEM; > + > + memcpy(msr_table, match_data->msr_table, > + match_data->msr_count * sizeof(struct meson_msr_id)); > + meson_msr.data.msr_table = msr_table; > + meson_msr.data.msr_count = match_data->msr_count; > > base = devm_platform_ioremap_resource(pdev, 0); > if (IS_ERR(base)) > return PTR_ERR(base); > > - priv->regmap = devm_regmap_init_mmio(&pdev->dev, base, > - &meson_clk_msr_regmap_config); > - if (IS_ERR(priv->regmap)) > - return PTR_ERR(priv->regmap); > + meson_msr.regmap = devm_regmap_init_mmio(&pdev->dev, base, > + &meson_clk_msr_regmap_config); > + if (IS_ERR(meson_msr.regmap)) > + return PTR_ERR(meson_msr.regmap); > > root = debugfs_create_dir("meson-clk-msr", NULL); > clks = debugfs_create_dir("clks", root); > > - debugfs_create_file("measure_summary", 0444, root, > - priv->msr_table, &clk_msr_summary_fops); > + debugfs_create_file("measure_summary", 0444, root, msr_table, > + &clk_msr_summary_fops); > > - for (i = 0 ; i < CLK_MSR_MAX ; ++i) { > - if (!priv->msr_table[i].name) > + for (i = 0 ; i < meson_msr.data.msr_count ; ++i) { > + if (!msr_table[i].name) > continue; > > - priv->msr_table[i].priv = priv; > - > - debugfs_create_file(priv->msr_table[i].name, 0444, clks, > - &priv->msr_table[i], &clk_msr_fops); > + debugfs_create_file(msr_table[i].name, 0444, clks, > + &msr_table[i], &clk_msr_fops); > } > > return 0; > } > > +static const struct meson_msr_data clk_msr_gx_data = { > + .msr_table = clk_msr_gx, > + .msr_count = ARRAY_SIZE(clk_msr_gx), > +}; > + > +static const struct meson_msr_data clk_msr_m8_data = { > + .msr_table = clk_msr_m8, > + .msr_count = ARRAY_SIZE(clk_msr_m8), > +}; > + > +static const struct meson_msr_data clk_msr_axg_data = { > + .msr_table = clk_msr_axg, > + .msr_count = ARRAY_SIZE(clk_msr_axg), > +}; > + > +static const struct meson_msr_data clk_msr_g12a_data = { > + .msr_table = clk_msr_g12a, > + .msr_count = ARRAY_SIZE(clk_msr_g12a), > +}; > + > +static const struct meson_msr_data clk_msr_sm1_data = { > + .msr_table = clk_msr_sm1, > + .msr_count = ARRAY_SIZE(clk_msr_sm1), > +}; > + > static const struct of_device_id meson_msr_match_table[] = { > { > .compatible = "amlogic,meson-gx-clk-measure", > - .data = (void *)clk_msr_gx, > + .data = &clk_msr_gx_data, > }, > { > .compatible = "amlogic,meson8-clk-measure", > - .data = (void *)clk_msr_m8, > + .data = &clk_msr_m8_data, > }, > { > .compatible = "amlogic,meson8b-clk-measure", > - .data = (void *)clk_msr_m8, > + .data = &clk_msr_m8_data, > }, > { > .compatible = "amlogic,meson-axg-clk-measure", > - .data = (void *)clk_msr_axg, > + .data = &clk_msr_axg_data, > }, > { > .compatible = "amlogic,meson-g12a-clk-measure", > - .data = (void *)clk_msr_g12a, > + .data = &clk_msr_g12a_data, > }, > { > .compatible = "amlogic,meson-sm1-clk-measure", > - .data = (void *)clk_msr_sm1, > + .data = &clk_msr_sm1_data, > }, > { /* sentinel */ } > }; > > --- > base-commit: 1e1fd26ed4ca05cc1f0e5857918da4dd54967f7d > change-id: 20250123-optimize_memory_size_of_clk_measure-f9c40e815794 > > Best regards, I think the goal is fine, but we should avoid any global variable to store the state and avoid initdata, but yes I agree to drop the fixed size tables and store the table size size in the compatible data. The solution would be to: - drop the MAX like you did - add a msr_count with ARRAY_SIZE like you did - but mark the compat data and table as const - in probe, allocate priv with a large table inside, & copy the data into it This should probably work and we could move the tables to read-only section. Neil