All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sergey Lisov <sleirsgoevy@gmail.com>
To: Ulf Hansson <ulf.hansson@linaro.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Alim Akhtar <alim.akhtar@samsung.com>,
	Jaehoon Chung <jh80.chung@samsung.com>
Cc: linux-mmc@vger.kernel.org, devicetree@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v5 2/3] mmc: dw_mmc: add an option to force 32-bit access to 64-bit FIFO
Date: Sun, 12 Mar 2023 20:58:50 +0300	[thread overview]
Message-ID: <640e1448.2e0a0220.365cb.1924@mx.google.com> (raw)

Some Samsung Exynos boards using the arm64 architecture have DW MMC
controllers configured for a 32-bit data bus but a 64-bit FIFO. On these
systems the 64-bit FIFO registers must be accessed in two 32-bit halves.
---
 drivers/mmc/host/dw_mmc-exynos.c |  43 ++++++++++-
 drivers/mmc/host/dw_mmc.c        | 122 ++++++++++++++++++++++++++++++-
 drivers/mmc/host/dw_mmc.h        |   2 +
 3 files changed, 164 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
index 9f20ac524..b4c0ba2eb 100644
--- a/drivers/mmc/host/dw_mmc-exynos.c
+++ b/drivers/mmc/host/dw_mmc-exynos.c
@@ -28,6 +28,8 @@ enum dw_mci_exynos_type {
 	DW_MCI_TYPE_EXYNOS5420_SMU,
 	DW_MCI_TYPE_EXYNOS7,
 	DW_MCI_TYPE_EXYNOS7_SMU,
+	DW_MCI_TYPE_EXYNOS78XX,
+	DW_MCI_TYPE_EXYNOS78XX_SMU,
 	DW_MCI_TYPE_ARTPEC8,
 };
 
@@ -70,6 +72,12 @@ static struct dw_mci_exynos_compatible {
 	}, {
 		.compatible	= "samsung,exynos7-dw-mshc-smu",
 		.ctrl_type	= DW_MCI_TYPE_EXYNOS7_SMU,
+	}, {
+		.compatible	= "samsung,exynos7885-dw-mshc",
+		.ctrl_type	= DW_MCI_TYPE_EXYNOS78XX,
+	}, {
+		.compatible	= "samsung,exynos7885-dw-mshc-smu",
+		.ctrl_type	= DW_MCI_TYPE_EXYNOS78XX_SMU,
 	}, {
 		.compatible	= "axis,artpec8-dw-mshc",
 		.ctrl_type	= DW_MCI_TYPE_ARTPEC8,
@@ -86,6 +94,8 @@ static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
 		return EXYNOS4210_FIXED_CIU_CLK_DIV;
 	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+			priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+			priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 			priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
 	else
@@ -101,7 +111,8 @@ static void dw_mci_exynos_config_smu(struct dw_mci *host)
 	 * set for non-ecryption mode at this time.
 	 */
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS5420_SMU ||
-		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU) {
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU) {
 		mci_writel(host, MPSBEGIN0, 0);
 		mci_writel(host, MPSEND0, SDMMC_ENDING_SEC_NR_MAX);
 		mci_writel(host, MPSCTRL0, SDMMC_MPSCTRL_SECURE_WRITE_BIT |
@@ -127,6 +138,12 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
 				DQS_CTRL_GET_RD_DELAY(priv->saved_strobe_ctrl);
 	}
 
+	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU) {
+		/* Quirk needed for certain Exynos SoCs */
+		host->quirks |= DW_MMC_QUIRK_FIFO64_32;
+	}
+
 	if (priv->ctrl_type == DW_MCI_TYPE_ARTPEC8) {
 		/* Quirk needed for the ARTPEC-8 SoC */
 		host->quirks |= DW_MMC_QUIRK_EXTENDED_TMOUT;
@@ -144,6 +161,8 @@ static void dw_mci_exynos_set_clksel_timing(struct dw_mci *host, u32 timing)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		clksel = mci_readl(host, CLKSEL64);
 	else
@@ -153,6 +172,8 @@ static void dw_mci_exynos_set_clksel_timing(struct dw_mci *host, u32 timing)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		mci_writel(host, CLKSEL64, clksel);
 	else
@@ -223,6 +244,8 @@ static int dw_mci_exynos_resume_noirq(struct device *dev)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		clksel = mci_readl(host, CLKSEL64);
 	else
@@ -231,6 +254,8 @@ static int dw_mci_exynos_resume_noirq(struct device *dev)
 	if (clksel & SDMMC_CLKSEL_WAKEUP_INT) {
 		if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+			priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+			priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 			priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 			mci_writel(host, CLKSEL64, clksel);
 		else
@@ -410,6 +435,8 @@ static inline u8 dw_mci_exynos_get_clksmpl(struct dw_mci *host)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		return SDMMC_CLKSEL_CCLK_SAMPLE(mci_readl(host, CLKSEL64));
 	else
@@ -423,6 +450,8 @@ static inline void dw_mci_exynos_set_clksmpl(struct dw_mci *host, u8 sample)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		clksel = mci_readl(host, CLKSEL64);
 	else
@@ -430,6 +459,8 @@ static inline void dw_mci_exynos_set_clksmpl(struct dw_mci *host, u8 sample)
 	clksel = SDMMC_CLKSEL_UP_SAMPLE(clksel, sample);
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		mci_writel(host, CLKSEL64, clksel);
 	else
@@ -444,6 +475,8 @@ static inline u8 dw_mci_exynos_move_next_clksmpl(struct dw_mci *host)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		clksel = mci_readl(host, CLKSEL64);
 	else
@@ -454,6 +487,8 @@ static inline u8 dw_mci_exynos_move_next_clksmpl(struct dw_mci *host)
 
 	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 		priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX ||
+		priv->ctrl_type == DW_MCI_TYPE_EXYNOS78XX_SMU ||
 		priv->ctrl_type == DW_MCI_TYPE_ARTPEC8)
 		mci_writel(host, CLKSEL64, clksel);
 	else
@@ -633,6 +668,12 @@ static const struct of_device_id dw_mci_exynos_match[] = {
 			.data = &exynos_drv_data, },
 	{ .compatible = "samsung,exynos7-dw-mshc-smu",
 			.data = &exynos_drv_data, },
+	/* XXX: more SoCs probably have the same quirk,
+		the compatible should be something more generic */
+	{ .compatible = "samsung,exynos7885-dw-mshc",
+			.data = &exynos_drv_data, },
+	{ .compatible = "samsung,exynos7885-dw-mshc-smu",
+			.data = &exynos_drv_data, },
 	{ .compatible = "axis,artpec8-dw-mshc",
 			.data = &artpec_drv_data, },
 	{},
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 581614196..9fe816c61 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -2575,6 +2575,119 @@ static void dw_mci_pull_data64(struct dw_mci *host, void *buf, int cnt)
 	}
 }
 
+/*
+  Some dw_mmc devices have 64-bit FIFOs, but expect them to be
+  accessed using two 32-bit accesses. If such controller is used
+  with a 64-bit kernel, this has to be done explicitly.
+
+  XXX: Is this issue specific to Exynos7?
+*/
+
+static inline uint64_t mci_fifo_readq_32(void __iomem *addr)
+{
+	uint64_t ans;
+	uint32_t proxy[2];
+
+	proxy[0] = mci_fifo_readl(addr);
+	proxy[1] = mci_fifo_readl(addr+4);
+	memcpy(&ans, proxy, 8);
+	return ans;
+}
+
+static inline void mci_fifo_writeq_32(void __iomem *addr, uint64_t value)
+{
+	uint32_t proxy[2];
+
+	memcpy(proxy, &value, 8);
+	mci_fifo_writel(addr, proxy[0]);
+	mci_fifo_writel(addr+4, proxy[1]);
+}
+
+static void dw_mci_push_data64_32(struct dw_mci *host, void *buf, int cnt)
+{
+	struct mmc_data *data = host->data;
+	int init_cnt = cnt;
+
+	/* try and push anything in the part_buf */
+	if (unlikely(host->part_buf_count)) {
+		int len = dw_mci_push_part_bytes(host, buf, cnt);
+
+		buf += len;
+		cnt -= len;
+
+		if (host->part_buf_count == 8) {
+			mci_fifo_writeq_32(host->fifo_reg, host->part_buf);
+			host->part_buf_count = 0;
+		}
+	}
+#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+	if (unlikely((unsigned long)buf & 0x7)) {
+		while (cnt >= 8) {
+			u64 aligned_buf[16];
+			int len = min(cnt & -8, (int)sizeof(aligned_buf));
+			int items = len >> 3;
+			int i;
+			/* memcpy from input buffer into aligned buffer */
+			memcpy(aligned_buf, buf, len);
+			buf += len;
+			cnt -= len;
+			/* push data from aligned buffer into fifo */
+			for (i = 0; i < items; ++i)
+				mci_fifo_writeq_32(host->fifo_reg, aligned_buf[i]);
+		}
+	} else
+#endif
+	{
+		u64 *pdata = buf;
+
+		for (; cnt >= 8; cnt -= 8)
+			mci_fifo_writeq_32(host->fifo_reg, *pdata++);
+		buf = pdata;
+	}
+	/* put anything remaining in the part_buf */
+	if (cnt) {
+		dw_mci_set_part_bytes(host, buf, cnt);
+		/* Push data if we have reached the expected data length */
+		if ((data->bytes_xfered + init_cnt) ==
+		    (data->blksz * data->blocks))
+			mci_fifo_writeq_32(host->fifo_reg, host->part_buf);
+	}
+}
+
+static void dw_mci_pull_data64_32(struct dw_mci *host, void *buf, int cnt)
+{
+#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+	if (unlikely((unsigned long)buf & 0x7)) {
+		while (cnt >= 8) {
+			/* pull data from fifo into aligned buffer */
+			u64 aligned_buf[16];
+			int len = min(cnt & -8, (int)sizeof(aligned_buf));
+			int items = len >> 3;
+			int i;
+
+			for (i = 0; i < items; ++i)
+				aligned_buf[i] = mci_fifo_readq_32(host->fifo_reg);
+
+			/* memcpy from aligned buffer into output buffer */
+			memcpy(buf, aligned_buf, len);
+			buf += len;
+			cnt -= len;
+		}
+	} else
+#endif
+	{
+		u64 *pdata = buf;
+
+		for (; cnt >= 8; cnt -= 8)
+			*pdata++ = mci_fifo_readq_32(host->fifo_reg);
+		buf = pdata;
+	}
+	if (cnt) {
+		host->part_buf = mci_fifo_readq_32(host->fifo_reg);
+		dw_mci_pull_final_bytes(host, buf, cnt);
+	}
+}
+
 static void dw_mci_pull_data(struct dw_mci *host, void *buf, int cnt)
 {
 	int len;
@@ -3367,8 +3480,13 @@ int dw_mci_probe(struct dw_mci *host)
 		width = 16;
 		host->data_shift = 1;
 	} else if (i == 2) {
-		host->push_data = dw_mci_push_data64;
-		host->pull_data = dw_mci_pull_data64;
+		if ((host->quirks & DW_MMC_QUIRK_FIFO64_32)) {
+			host->push_data = dw_mci_push_data64_32;
+			host->pull_data = dw_mci_pull_data64_32;
+		} else {
+			host->push_data = dw_mci_push_data64;
+			host->pull_data = dw_mci_pull_data64;
+		}
 		width = 64;
 		host->data_shift = 3;
 	} else {
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 4ed81f94f..edd642b92 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -280,6 +280,8 @@ struct dw_mci_board {
 
 /* Support for longer data read timeout */
 #define DW_MMC_QUIRK_EXTENDED_TMOUT            BIT(0)
+/* Force 32-bit access to the FIFO */
+#define DW_MMC_QUIRK_FIFO64_32                 BIT(1)
 
 #define DW_MMC_240A		0x240a
 #define DW_MMC_280A		0x280a
-- 
2.38.3



             reply	other threads:[~2023-03-12 18:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-12 17:58 Sergey Lisov [this message]
  -- strict thread matches above, loose matches on Subject: below --
2023-03-12 17:58 [PATCH v5 0/3] mmc: dw_mmc: fix DW MMC cores with 32-bit bus on 64-bit Linux systems Sergey Lisov
2023-03-12 17:58 ` [PATCH v5 2/3] mmc: dw_mmc: add an option to force 32-bit access to 64-bit FIFO Sergey Lisov
2023-03-12 17:58   ` Sergey Lisov
2023-03-12 17:58 Sergey Lisov
2023-03-12 17:58 Sergey Lisov
2023-03-12 17:58 Sergey Lisov
2023-03-12 17:58 Sergey Lisov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=640e1448.2e0a0220.365cb.1924@mx.google.com \
    --to=sleirsgoevy@gmail.com \
    --cc=alim.akhtar@samsung.com \
    --cc=devicetree@vger.kernel.org \
    --cc=jh80.chung@samsung.com \
    --cc=krzysztof.kozlowski+dt@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mmc@vger.kernel.org \
    --cc=linux-samsung-soc@vger.kernel.org \
    --cc=robh+dt@kernel.org \
    --cc=ulf.hansson@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.