From patchwork Wed Aug 14 22:34:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Detlev Casanova X-Patchwork-Id: 13764233 Received: from sender4-op-o14.zoho.com (sender4-op-o14.zoho.com [136.143.188.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 85E6B60B96; Wed, 14 Aug 2024 22:35:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.14 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723674904; cv=pass; b=RkaIET/gDR0YDCd1hgcq8Y+cWm7pKf7QT+NwXqSF9AkcFtnATsNfI+kP0YoetTcNHDpweTDgVtIL5InhKyqDGT3XqsXwSchtyqiZGT/dBGOFB1n0md28PTOyT3sXcYevkKokF5CPwvDawKd3RBi4PcVNqT1YJLMBep3EPK7vtY4= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723674904; c=relaxed/simple; bh=lt9QrNAThuMnmsDhWCTY7drPRB+TIQjRb++6AHrZCqM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=j2uedlAbc1N6ThH3cUEh19Xu0SzmWJI/WFXiUME1ncvJUsrq2AkqH6eXNDCzp3pcFg03r6bLcIHGX8i4tID4kLaeOhG/9V0ya1N8ogEAaWLFQRL0bWj6k3C/+Ew1W5/Hg1wRbMj2tNc2oO6AJizOuKEOujxbLI4yxhAv1txyQek= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=detlev.casanova@collabora.com header.b=aokBFlIM; arc=pass smtp.client-ip=136.143.188.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=detlev.casanova@collabora.com header.b="aokBFlIM" ARC-Seal: i=1; a=rsa-sha256; t=1723674877; cv=none; d=zohomail.com; s=zohoarc; b=EGSXNJEBxi9LLaZ2ZqW649n43+gqF8arv7DpwOIiIL16QzqBapIF5E2VgyND5qvIboPAN0TsYRSKIarbp2+tHPrPv/4dAK0I77DwHaMY7XcLgh6I3+PzHeLO8p+zOTRpdlAEwyAxJAzEz6pbSo0LJjEtjPrn1B5NONdXDPuwhzI= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1723674877; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=nwZ71hZV+gNmLOh0K/QZssl4osS7eYQruaBZZmkWuuQ=; b=Td6ViPYjs+uK4BES46eCH2M5/sYR8WzXLZTgRHxRq2Ove0nPUyxDSyV4F6HYbK6DPlXo8/XSp4gARbWDkuIjIBpg6y8rV7NulJXCfo4nn8rtwDEdZljD6LIiB/5+qdik8E2YKKQEQZ/DCF7vd5peOLSGW00JYSJaxHTqkjRCIco= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=detlev.casanova@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1723674877; s=zohomail; d=collabora.com; i=detlev.casanova@collabora.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=nwZ71hZV+gNmLOh0K/QZssl4osS7eYQruaBZZmkWuuQ=; b=aokBFlIMffe/NRZYt2Jj3YcNpdc4Gw/BcWuNVpzP03Kz/U/tEHFrrJ5CGNh67cP5 tQ8adU12R9N5YZ/gQS+n0Vqc/XESxhP4TYALYoacSiLyu56kDGDp0sh6k1HKWXjlSl1 +SMJxrXhrJ9Erdf9SZSvAVu7LW8JcmrFlxZ9RAFM= Received: by mx.zohomail.com with SMTPS id 17236748749611007.2751147530727; Wed, 14 Aug 2024 15:34:34 -0700 (PDT) From: Detlev Casanova To: linux-kernel@vger.kernel.org Cc: Ulf Hansson , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner , Jaehoon Chung , linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, kernel@collabora.com, Shawn Lin , Detlev Casanova Subject: [PATCH v3 3/3] mmc: dw_mmc-rockchip: Add internal phase support Date: Wed, 14 Aug 2024 18:34:02 -0400 Message-ID: <20240814223555.3695-4-detlev.casanova@collabora.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240814223555.3695-1-detlev.casanova@collabora.com> References: <20240814223555.3695-1-detlev.casanova@collabora.com> Precedence: bulk X-Mailing-List: linux-mmc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ZohoMailClient: External From: Shawn Lin Some Rockchip devices put the phase settings into the dw_mmc controller. The feature is implemented in devices where the USRID register contains 0x20230002. Signed-off-by: Shawn Lin Signed-off-by: Detlev Casanova Acked-by: Shawn Lin --- drivers/mmc/host/dw_mmc-rockchip.c | 184 ++++++++++++++++++++++++++--- 1 file changed, 170 insertions(+), 14 deletions(-) diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c index 367633f4e8892..03e25a8b8a305 100644 --- a/drivers/mmc/host/dw_mmc-rockchip.c +++ b/drivers/mmc/host/dw_mmc-rockchip.c @@ -16,6 +16,17 @@ #include "dw_mmc-pltfm.h" #define RK3288_CLKGEN_DIV 2 +#define USRID_INTER_PHASE 0x20230001 +#define SDMMC_TIMING_CON0 0x130 +#define SDMMC_TIMING_CON1 0x134 +#define ROCKCHIP_MMC_DELAY_SEL BIT(10) +#define ROCKCHIP_MMC_DEGREE_MASK 0x3 +#define ROCKCHIP_MMC_DELAYNUM_OFFSET 2 +#define ROCKCHIP_MMC_DELAYNUM_MASK (0xff << ROCKCHIP_MMC_DELAYNUM_OFFSET) +#define PSECS_PER_SEC 1000000000000LL +#define ROCKCHIP_MMC_DELAY_ELEMENT_PSEC 60 +#define HIWORD_UPDATE(val, mask, shift) \ + ((val) << (shift) | (mask) << ((shift) + 16)) static const unsigned int freqs[] = { 100000, 200000, 300000, 400000 }; @@ -25,9 +36,121 @@ struct dw_mci_rockchip_priv_data { int default_sample_phase; int num_phases; bool use_v2_tuning; + int usrid; int last_degree; }; +/* + * Each fine delay is between 44ps-77ps. Assume each fine delay is 60ps to + * simplify calculations. So 45degs could be anywhere between 33deg and 57.8deg. + */ +static int rockchip_mmc_get_phase(struct dw_mci *host, bool sample) +{ + unsigned long rate = clk_get_rate(host->ciu_clk); + u32 raw_value; + u16 degrees; + u32 delay_num = 0; + + /* Constant signal, no measurable phase shift */ + if (!rate) + return 0; + + if (sample) + raw_value = mci_readl(host, TIMING_CON1) >> 1; + else + raw_value = mci_readl(host, TIMING_CON0) >> 1; + + degrees = (raw_value & ROCKCHIP_MMC_DEGREE_MASK) * 90; + + if (raw_value & ROCKCHIP_MMC_DELAY_SEL) { + /* degrees/delaynum * 1000000 */ + unsigned long factor = (ROCKCHIP_MMC_DELAY_ELEMENT_PSEC / 10) * + 36 * (rate / 10000); + + delay_num = (raw_value & ROCKCHIP_MMC_DELAYNUM_MASK); + delay_num >>= ROCKCHIP_MMC_DELAYNUM_OFFSET; + degrees += DIV_ROUND_CLOSEST(delay_num * factor, 1000000); + } + + return degrees % 360; +} + +static int rockchip_mmc_set_phase(struct dw_mci *host, bool sample, int degrees) +{ + unsigned long rate = clk_get_rate(host->ciu_clk); + u8 nineties, remainder; + u8 delay_num; + u32 raw_value; + u32 delay; + + /* + * The below calculation is based on the output clock from + * MMC host to the card, which expects the phase clock inherits + * the clock rate from its parent, namely the output clock + * provider of MMC host. However, things may go wrong if + * (1) It is orphan. + * (2) It is assigned to the wrong parent. + * + * This check help debug the case (1), which seems to be the + * most likely problem we often face and which makes it difficult + * for people to debug unstable mmc tuning results. + */ + if (!rate) { + dev_err(host->dev, "%s: invalid clk rate\n", __func__); + return -EINVAL; + } + + nineties = degrees / 90; + remainder = (degrees % 90); + + /* + * Due to the inexact nature of the "fine" delay, we might + * actually go non-monotonic. We don't go _too_ monotonic + * though, so we should be OK. Here are options of how we may + * work: + * + * Ideally we end up with: + * 1.0, 2.0, ..., 69.0, 70.0, ..., 89.0, 90.0 + * + * On one extreme (if delay is actually 44ps): + * .73, 1.5, ..., 50.6, 51.3, ..., 65.3, 90.0 + * The other (if delay is actually 77ps): + * 1.3, 2.6, ..., 88.6. 89.8, ..., 114.0, 90 + * + * It's possible we might make a delay that is up to 25 + * degrees off from what we think we're making. That's OK + * though because we should be REALLY far from any bad range. + */ + + /* + * Convert to delay; do a little extra work to make sure we + * don't overflow 32-bit / 64-bit numbers. + */ + delay = 10000000; /* PSECS_PER_SEC / 10000 / 10 */ + delay *= remainder; + delay = DIV_ROUND_CLOSEST(delay, + (rate / 1000) * 36 * + (ROCKCHIP_MMC_DELAY_ELEMENT_PSEC / 10)); + + delay_num = (u8) min_t(u32, delay, 255); + + raw_value = delay_num ? ROCKCHIP_MMC_DELAY_SEL : 0; + raw_value |= delay_num << ROCKCHIP_MMC_DELAYNUM_OFFSET; + raw_value |= nineties; + + if (sample) + mci_writel(host, TIMING_CON1, HIWORD_UPDATE(raw_value, 0x07ff, 1)); + else + mci_writel(host, TIMING_CON0, HIWORD_UPDATE(raw_value, 0x07ff, 1)); + + dev_dbg(host->dev, "set %s_phase(%d) delay_nums=%u actual_degrees=%d\n", + sample ? "sample" : "drv", degrees, delay_num, + rockchip_mmc_get_phase(host, sample) + ); + + return 0; +} + static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) { struct dw_mci_rockchip_priv_data *priv = host->priv; @@ -65,8 +188,12 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) } /* Make sure we use phases which we can enumerate with */ - if (!IS_ERR(priv->sample_clk) && ios->timing <= MMC_TIMING_SD_HS) - clk_set_phase(priv->sample_clk, priv->default_sample_phase); + if (!IS_ERR(priv->sample_clk) && ios->timing <= MMC_TIMING_SD_HS) { + if (priv->usrid == USRID_INTER_PHASE) + rockchip_mmc_set_phase(host, true, priv->default_sample_phase); + else + clk_set_phase(priv->sample_clk, priv->default_sample_phase); + } /* * Set the drive phase offset based on speed mode to achieve hold times. @@ -129,7 +256,10 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios) break; } - clk_set_phase(priv->drv_clk, phase); + if (priv->usrid == USRID_INTER_PHASE) + rockchip_mmc_set_phase(host, false, phase); + else + clk_set_phase(priv->drv_clk, phase); } } @@ -141,13 +271,16 @@ static int dw_mci_v2_execute_tuning(struct dw_mci_slot *slot, u32 opcode) struct dw_mci *host = slot->host; struct dw_mci_rockchip_priv_data *priv = host->priv; struct mmc_host *mmc = slot->mmc; - u32 degrees[4] = {90, 180, 270, 360}; + u32 degree, degrees[4] = {90, 180, 270, 360}; int i; static bool inherit = true; if (inherit) { inherit = false; - i = clk_get_phase(priv->sample_clk) / 90 - 1; + if (priv->usrid == USRID_INTER_PHASE) + i = rockchip_mmc_get_phase(host, true) / 90; + else + i = clk_get_phase(priv->sample_clk) / 90 - 1; goto done; } @@ -156,7 +289,11 @@ static int dw_mci_v2_execute_tuning(struct dw_mci_slot *slot, u32 opcode) if (degrees[i] == priv->last_degree) continue; - clk_set_phase(priv->sample_clk, degrees[i]); + degree = (degrees[i] + priv->last_degree + 90) % 360; + if (priv->usrid == USRID_INTER_PHASE) + rockchip_mmc_set_phase(host, true, degree); + else + clk_set_phase(priv->sample_clk, degree); if (!mmc_send_tuning(mmc, opcode, NULL)) break; } @@ -189,6 +326,7 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) int longest_range_len = -1; int longest_range = -1; int middle_phase; + int phase; if (IS_ERR(priv->sample_clk)) { dev_err(host->dev, "Tuning clock (sample_clk) not defined.\n"); @@ -209,8 +347,15 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) /* Try each phase and extract good ranges */ for (i = 0; i < priv->num_phases; ) { - clk_set_phase(priv->sample_clk, - TUNING_ITERATION_TO_PHASE(i, priv->num_phases)); + /* Cannot guarantee any phases larger than 270 would work well */ + if (TUNING_ITERATION_TO_PHASE(i, priv->num_phases) > 270) + break; + if (priv->usrid == USRID_INTER_PHASE) + rockchip_mmc_set_phase(host, true, + TUNING_ITERATION_TO_PHASE(i, priv->num_phases)); + else + clk_set_phase(priv->sample_clk, + TUNING_ITERATION_TO_PHASE(i, priv->num_phases)); v = !mmc_send_tuning(mmc, opcode, NULL); @@ -256,7 +401,10 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) } if (ranges[0].start == 0 && ranges[0].end == priv->num_phases - 1) { - clk_set_phase(priv->sample_clk, priv->default_sample_phase); + if (priv->usrid == USRID_INTER_PHASE) + rockchip_mmc_set_phase(host, true, priv->default_sample_phase); + else + clk_set_phase(priv->sample_clk, priv->default_sample_phase); dev_info(host->dev, "All phases work, using default phase %d.", priv->default_sample_phase); goto free; @@ -293,12 +441,13 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode) middle_phase = ranges[longest_range].start + longest_range_len / 2; middle_phase %= priv->num_phases; - dev_info(host->dev, "Successfully tuned phase to %d\n", - TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases)); + phase = TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases); + dev_info(host->dev, "Successfully tuned phase to %d\n", phase); - clk_set_phase(priv->sample_clk, - TUNING_ITERATION_TO_PHASE(middle_phase, - priv->num_phases)); + if (priv->usrid == USRID_INTER_PHASE) + rockchip_mmc_set_phase(host, true, phase); + else + clk_set_phase(priv->sample_clk, phase); free: kfree(ranges); @@ -342,6 +491,7 @@ static int dw_mci_rk3288_parse_dt(struct dw_mci *host) static int dw_mci_rockchip_init(struct dw_mci *host) { int ret, i; + struct dw_mci_rockchip_priv_data *priv = host->priv; /* It is slot 8 on Rockchip SoCs */ host->sdio_id0 = 8; @@ -365,6 +515,12 @@ static int dw_mci_rockchip_init(struct dw_mci *host) dev_warn(host->dev, "no valid minimum freq: %d\n", ret); } + priv->usrid = mci_readl(host, USRID); + if (priv->usrid == USRID_INTER_PHASE) { + priv->sample_clk = NULL; + priv->drv_clk = NULL; + } + return 0; }