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* [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface
@ 2020-07-10 11:08 Ben Chuang
  2020-08-18 11:41 ` Ulf Hansson
  0 siblings, 1 reply; 5+ messages in thread
From: Ben Chuang @ 2020-07-10 11:08 UTC (permalink / raw)
  To: adrian.hunter, ulf.hansson
  Cc: linux-mmc, linux-kernel, ben.chuang, takahiro.akashi, greg.tu,
	Ben Chuang

From: Ben Chuang <ben.chuang@genesyslogic.com.tw>

The flow of "interface selection and initialization" was a bit modified
for UHS-II card. This commit follows the sequence defined in SD
specification (Part 1).
See section 7.2.3 in "UHS-II Simplified Addendum."

Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
 drivers/mmc/core/Makefile |   2 +-
 drivers/mmc/core/bus.c    |   5 +-
 drivers/mmc/core/core.c   |  33 +-
 drivers/mmc/core/sd.c     |  26 ++
 drivers/mmc/core/uhs2.c   | 800 ++++++++++++++++++++++++++++++++++++++
 drivers/mmc/core/uhs2.h   |  20 +
 6 files changed, 882 insertions(+), 4 deletions(-)
 create mode 100644 drivers/mmc/core/uhs2.c
 create mode 100644 drivers/mmc/core/uhs2.h

diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
index 95ffe008ebdf..e2a90dc98afc 100644
--- a/drivers/mmc/core/Makefile
+++ b/drivers/mmc/core/Makefile
@@ -8,7 +8,7 @@ mmc_core-y			:= core.o bus.o host.o \
 				   mmc.o mmc_ops.o sd.o sd_ops.o \
 				   sdio.o sdio_ops.o sdio_bus.o \
 				   sdio_cis.o sdio_io.o sdio_irq.o \
-				   slot-gpio.o regulator.o
+				   slot-gpio.o regulator.o uhs2.o
 mmc_core-$(CONFIG_OF)		+= pwrseq.o
 obj-$(CONFIG_PWRSEQ_SIMPLE)	+= pwrseq_simple.o
 obj-$(CONFIG_PWRSEQ_SD8787)	+= pwrseq_sd8787.o
diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
index 70207f11a654..66d3e942f3fc 100644
--- a/drivers/mmc/core/bus.c
+++ b/drivers/mmc/core/bus.c
@@ -350,8 +350,9 @@ int mmc_add_card(struct mmc_card *card)
 	} else {
 		pr_info("%s: new %s%s%s%s%s%s card at address %04x\n",
 			mmc_hostname(card->host),
-			mmc_card_uhs(card) ? "ultra high speed " :
-			(mmc_card_hs(card) ? "high speed " : ""),
+			mmc_card_uhs2(card) ? "ultra high speed 2 " :
+			(mmc_card_uhs(card) ? "ultra high speed 1 " :
+			(mmc_card_hs(card) ? "high speed " : "")),
 			mmc_card_hs400(card) ? "HS400 " :
 			(mmc_card_hs200(card) ? "HS200 " : ""),
 			mmc_card_hs400es(card) ? "Enhanced strobe " : "",
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index c6540d56646b..e2534f3446ce 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -31,6 +31,7 @@
 #include <linux/mmc/mmc.h>
 #include <linux/mmc/sd.h>
 #include <linux/mmc/slot-gpio.h>
+#include <linux/mmc/uhs2.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/mmc.h>
@@ -41,6 +42,7 @@
 #include "host.h"
 #include "sdio_bus.h"
 #include "pwrseq.h"
+#include "uhs2.h"
 
 #include "mmc_ops.h"
 #include "sd_ops.h"
@@ -51,6 +53,7 @@
 #define SD_DISCARD_TIMEOUT_MS	(250)
 
 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
+static const unsigned int uhs2_freqs[] = { 52000000, 26000000 };
 
 /*
  * Enabling software CRCs on the data blocks can be a significant (30%)
@@ -2165,9 +2168,10 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 		if (!mmc_attach_sdio(host))
 			return 0;
 
-	if (!(host->caps2 & MMC_CAP2_NO_SD))
+	if (!(host->caps2 & MMC_CAP2_NO_SD)) {
 		if (!mmc_attach_sd(host))
 			return 0;
+	}
 
 	if (!(host->caps2 & MMC_CAP2_NO_MMC))
 		if (!mmc_attach_mmc(host))
@@ -2300,6 +2304,33 @@ void mmc_rescan(struct work_struct *work)
 		goto out;
 	}
 
+	if (host->caps & MMC_CAP_UHS2) {
+		/*
+		 * Start to try UHS-II initialization from 52MHz to 26MHz
+		 * (RCLK range) per spec.
+		 */
+		for (i = 0; i < ARRAY_SIZE(uhs2_freqs); i++) {
+			unsigned int freq = uhs2_freqs[i];
+			int err;
+
+			err = mmc_uhs2_rescan_try_freq(host,
+						       max(freq, host->f_min));
+			if (!err) {
+				mmc_release_host(host);
+				goto out;
+			}
+
+			if (err == UHS2_PHY_INIT_ERR)
+				/* UHS2 IF detect or Lane Sync error.
+				 * Try legacy interface.
+				 */
+				break;
+
+			if (freq <= host->f_min)
+				break;
+		}
+	}
+
 	for (i = 0; i < ARRAY_SIZE(freqs); i++) {
 		unsigned int freq = freqs[i];
 		if (freq > host->f_max) {
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 5a2210c25aa7..c5b071bd98b3 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -901,6 +901,20 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
 		err = mmc_read_switch(card);
 		if (err)
 			return err;
+		if (host->flags & MMC_UHS2_INITIALIZED) {
+			u8 status[64];
+			/*
+			 * send CMD6 to set Maximum Power Consumption
+			 * to get better performance
+			 */
+			err = mmc_sd_switch(card, 0, 3,
+					    SD_SET_CURRENT_LIMIT_1000, status);
+			if (!err) {
+				err = mmc_sd_switch(card, 1, 3,
+						    SD_SET_CURRENT_LIMIT_1000,
+						    status);
+			}
+		}
 	}
 
 	/*
@@ -1043,6 +1057,11 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
 	if (err)
 		goto free_card;
 
+	/* For UHS2, skip the UHS-I initialization. */
+	if ((host->flags & MMC_UHS2_SUPPORT) &&
+	    (host->flags & MMC_UHS2_INITIALIZED))
+		goto done;
+
 	/*
 	 * If the card has not been power cycled, it may still be using 1.8V
 	 * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
@@ -1334,6 +1353,13 @@ int mmc_attach_sd(struct mmc_host *host)
 
 	rocr = mmc_select_voltage(host, ocr);
 
+	/*
+	 * Some cards have zero value of rocr in UHS-II mode. Assign host's ocr
+	 * value to rocr.
+	 */
+	if ((host->flags & MMC_UHS2_INITIALIZED) && !rocr)
+		rocr = host->ocr_avail;
+
 	/*
 	 * Can we support the voltage(s) of the card(s)?
 	 */
diff --git a/drivers/mmc/core/uhs2.c b/drivers/mmc/core/uhs2.c
new file mode 100644
index 000000000000..a3b20ac6f315
--- /dev/null
+++ b/drivers/mmc/core/uhs2.c
@@ -0,0 +1,800 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  linux/drivers/mmc/core/uhs2.c - UHS-II driver
+ *
+ *  Copyright (C) 2014 Intel Corp, All Rights Reserved.
+ *  Copyright (C) 2020 Genesys Logic, Inc.
+ *  Authors: Ben Chuang <ben.chuang@genesyslogic.com.tw>
+ *  Copyright (C) 2020 Linaro Limited
+ *  Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ */
+
+#include <asm/byteorder.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mmc/core.h>
+#include <linux/mmc/sdio.h>
+#include <linux/mmc/slot-gpio.h>
+#include <linux/mmc/uhs2.h>
+
+#include "uhs2.h"
+#include "mmc_ops.h"
+#include "sd_ops.h"
+#include "core.h"
+
+#define DBG(f, x...) \
+	pr_warn("[%s()]: " f, __func__, ## x)
+
+/**
+ * uhs2_cmd_assemble - assemble and build up uhs2 command
+ * @cmd:	MMC command
+ * @uhs2_cmd:	UHS2 command
+ * @header:	Value of packet header
+ * @arg:	Argument of packet
+ * @payload:	Payload of packet
+ * @plen:	Payload length
+ * @resp:	Buffer for response
+ * @resp_len:	Response buffer length
+ *
+ * resp is inputted outside which should be a variable created by caller
+ * so caller should handle it. For SD command, there is no uhs2_resp and
+ * response should be stored in resp of mmc_command.
+ */
+static void uhs2_cmd_assemble(struct mmc_command *cmd,
+			      struct uhs2_command *uhs2_cmd,
+			      u16 header, u16 arg,
+			      u32 *payload, u8 plen, u8 *resp, u8 resp_len)
+{
+	uhs2_cmd->header = header;
+	uhs2_cmd->arg = arg;
+	uhs2_cmd->payload = payload;
+	uhs2_cmd->payload_len = plen * sizeof(u32);
+	uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
+
+	cmd->uhs2_cmd = uhs2_cmd;
+	cmd->uhs2_resp = resp;
+	cmd->uhs2_resp_len = resp_len;
+
+	pr_debug("%s: uhs2_cmd: header=0x%x arg=0x%x\n",
+		 __func__, uhs2_cmd->header, uhs2_cmd->arg);
+	pr_debug("%s:           payload_len=%d packet_len=%d resp_len=%d\n",
+		 __func__, uhs2_cmd->payload_len, uhs2_cmd->packet_len,
+		cmd->uhs2_resp_len);
+}
+
+static int uhs2_dev_init(struct mmc_host *host)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u32 cnt;
+	u32 dap, gap, gap1;
+	u16 header = 0, arg = 0;
+	u32 payload[1];
+	u8 plen = 1;
+	u8 gd = 0, cf = 1;
+	u8 resp[6] = {0};
+	u8 resp_len = 6;
+	int err;
+
+	dap = host->uhs2_caps.dap;
+	gap = host->uhs2_caps.gap;
+
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
+	arg = ((UHS2_DEV_CMD_DEVICE_INIT & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_4B |
+		(UHS2_DEV_CMD_DEVICE_INIT >> 8);
+
+	/* need this for some cards */
+	cmd.busy_timeout = 1000;
+
+	for (cnt = 0; cnt < 30; cnt++) {
+		payload[0] = ((dap & 0xF) << 12) |
+			(cf << 11) |
+			((gd & 0xF) << 4) |
+			(gap & 0xF);
+
+		uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
+				  payload, plen, resp, resp_len);
+
+		DBG("Begin DEVICE_INIT, header=0x%x, arg=0x%x, payload=0x%x.\n",
+		    header, arg, payload[0]);
+
+		DBG("Sending DEVICE_INIT. Count = %d\n", cnt);
+		err = mmc_wait_for_cmd(host, &cmd, 0);
+
+		if (err) {
+			pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+			       mmc_hostname(host), __func__, err);
+			return -EIO;
+		}
+
+		if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
+			int i;
+
+			pr_warn("%s: DEVICE_INIT response is: ",
+				mmc_hostname(host));
+			for (i = 0; i < resp_len; i++)
+				pr_warn("0x%x ", resp[i]);
+			pr_warn("\n");
+		}
+
+		if (resp[3] != (UHS2_DEV_CMD_DEVICE_INIT & 0xFF)) {
+			pr_err("%s: DEVICE_INIT response is wrong!\n",
+			       mmc_hostname(host));
+			return -EIO;
+		}
+
+		if (resp[5] & 0x8) {
+			DBG("CF is set, device is initialized!\n");
+			host->group_desc = gd;
+			break;
+		}
+		gap1 = resp[4] & 0x0F;
+		if (gap == gap1)
+			gd++;
+	}
+	if (cnt == 30) {
+		pr_err("%s: DEVICE_INIT fail, already 30 times!\n",
+		       mmc_hostname(host));
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int uhs2_enum(struct mmc_host *host)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 payload[1];
+	u8 plen = 1;
+	u8 id_f = 0xF, id_l = 0x0;
+	u8 resp[8] = {0};
+	u8 resp_len = 8;
+	int err;
+
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
+	arg = ((UHS2_DEV_CMD_ENUMERATE & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_4B |
+		(UHS2_DEV_CMD_ENUMERATE >> 8);
+
+	payload[0] = (id_f << 4) | id_l;
+
+	DBG("Begin ENUMERATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
+	    header, arg, payload[0]);
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  resp, resp_len);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
+		int i;
+
+		pr_warn("%s: ENUMERATE response is: ", mmc_hostname(host));
+		for (i = 0; i < resp_len; i++)
+			pr_warn("0x%x ", resp[i]);
+		pr_warn("\n");
+	}
+
+	if (resp[3] != (UHS2_DEV_CMD_ENUMERATE & 0xFF)) {
+		pr_err("%s: ENUMERATE response is wrong!\n",
+		       mmc_hostname(host));
+		return -EIO;
+	}
+
+	id_f = (resp[4] >> 4) & 0xF;
+	id_l = resp[4] & 0xF;
+	DBG("id_f = %d, id_l = %d.\n", id_f, id_l);
+	DBG("Enumerate Cmd Completed. No. of Devices connected = %d\n",
+	    id_l - id_f + 1);
+	host->uhs2_dev_prop.node_id = id_f;
+
+	return 0;
+}
+
+static int uhs2_config_read(struct mmc_host *host)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 cap;
+	int err;
+
+	DBG("INQUIRY_CFG: read Generic Caps.\n");
+	header = UHS2_NATIVE_PACKET |
+		 UHS2_PACKET_TYPE_CCMD |
+		 host->uhs2_dev_prop.node_id;
+	arg = ((UHS2_DEV_CONFIG_GEN_CAPS & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_READ |
+		UHS2_NATIVE_CMD_PLEN_4B |
+		(UHS2_DEV_CONFIG_GEN_CAPS >> 8);
+
+	DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
+	    header, arg);
+	/* There is no payload because per spec, there should be
+	 * no payload field for read CCMD.
+	 * Plen is set in arg. Per spec, plen for read CCMD
+	 * represents the len of read data which is assigned in payload
+	 * of following RES (p136).
+	 */
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
+		int i;
+
+		pr_warn("%s: INQUIRY_CFG generic response is: ",
+			mmc_hostname(host));
+		for (i = 0; i < 2; i++)
+			pr_warn("0x%x ", cmd.resp[i]);
+		pr_warn("\n");
+	}
+
+	cap = cmd.resp[0];
+	DBG("Device Generic Caps (0-31) is: 0x%x.\n", cap);
+	host->uhs2_dev_prop.n_lanes = (cap >> UHS2_DEV_CONFIG_N_LANES_POS) &
+					UHS2_DEV_CONFIG_N_LANES_MASK;
+	host->uhs2_dev_prop.dadr_len = (cap >> UHS2_DEV_CONFIG_DADR_POS) &
+					UHS2_DEV_CONFIG_DADR_MASK;
+	host->uhs2_dev_prop.app_type = (cap >> UHS2_DEV_CONFIG_APP_POS) &
+					UHS2_DEV_CONFIG_APP_MASK;
+
+	DBG("INQUIRY_CFG: read PHY Caps.\n");
+	arg = ((UHS2_DEV_CONFIG_PHY_CAPS & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_READ |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_PHY_CAPS >> 8);
+
+	DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
+	    header, arg);
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
+		int i;
+
+		pr_warn("%s: INQUIRY_CFG PHY response is: ",
+			mmc_hostname(host));
+		for (i = 0; i < 2; i++)
+			pr_warn("0x%x ", cmd.resp[i]);
+		pr_warn("\n");
+	}
+
+	cap = cmd.resp[0];
+	DBG("Device PHY Caps (0-31) is: 0x%x.\n", cap);
+	host->uhs2_dev_prop.phy_minor_rev = cap &
+					UHS2_DEV_CONFIG_PHY_MINOR_MASK;
+	host->uhs2_dev_prop.phy_major_rev = (cap >>
+					UHS2_DEV_CONFIG_PHY_MAJOR_POS) &
+					UHS2_DEV_CONFIG_PHY_MAJOR_MASK;
+	host->uhs2_dev_prop.can_hibernate = (cap >>
+					UHS2_DEV_CONFIG_CAN_HIBER_POS) &
+					UHS2_DEV_CONFIG_CAN_HIBER_MASK;
+
+	cap = cmd.resp[1];
+	DBG("Device PHY Caps (32-63) is: 0x%x.\n", cap);
+	host->uhs2_dev_prop.n_lss_sync = cap & UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
+	host->uhs2_dev_prop.n_lss_dir = (cap >>
+					UHS2_DEV_CONFIG_N_LSS_DIR_POS) &
+					UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+	if (host->uhs2_dev_prop.n_lss_sync == 0)
+		host->uhs2_dev_prop.n_lss_sync = 16 << 2;
+	else
+		host->uhs2_dev_prop.n_lss_sync <<= 2;
+
+	if (host->uhs2_dev_prop.n_lss_dir == 0)
+		host->uhs2_dev_prop.n_lss_dir = 16 << 3;
+	else
+		host->uhs2_dev_prop.n_lss_dir <<= 3;
+
+	DBG("INQUIRY_CFG: read LINK-TRAN Caps.\n");
+	arg = ((UHS2_DEV_CONFIG_LINK_TRAN_CAPS & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_READ |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_LINK_TRAN_CAPS >> 8);
+
+	DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
+	    header, arg);
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
+		int i;
+
+		pr_warn("%s: INQUIRY_CFG Link-Tran response is: ",
+			mmc_hostname(host));
+		for (i = 0; i < 2; i++)
+			pr_warn("0x%x ", cmd.resp[i]);
+		pr_warn("\n");
+	}
+
+	cap = cmd.resp[0];
+	DBG("Device LINK-TRAN Caps (0-31) is: 0x%x.\n", cap);
+	host->uhs2_dev_prop.link_minor_rev = cap &
+					UHS2_DEV_CONFIG_LT_MINOR_MASK;
+	host->uhs2_dev_prop.link_major_rev = (cap >>
+					UHS2_DEV_CONFIG_LT_MAJOR_POS) &
+					UHS2_DEV_CONFIG_LT_MAJOR_MASK;
+	host->uhs2_dev_prop.n_fcu = (cap >> UHS2_DEV_CONFIG_N_FCU_POS) &
+					UHS2_DEV_CONFIG_N_FCU_MASK;
+	host->uhs2_dev_prop.dev_type = (cap >> UHS2_DEV_CONFIG_DEV_TYPE_POS) &
+					UHS2_DEV_CONFIG_DEV_TYPE_MASK;
+	host->uhs2_dev_prop.maxblk_len = (cap >>
+					UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) &
+					UHS2_DEV_CONFIG_MAX_BLK_LEN_MASK;
+
+	cap = cmd.resp[1];
+	DBG("Device LINK-TRAN Caps (32-63) is: 0x%x.\n", cap);
+	host->uhs2_dev_prop.n_data_gap = cap & UHS2_DEV_CONFIG_N_DATA_GAP_MASK;
+	if (host->uhs2_dev_prop.n_fcu == 0)
+		host->uhs2_dev_prop.n_fcu = 256;
+
+	return 0;
+}
+
+static int uhs2_config_write(struct mmc_host *host)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 nTry;
+	u32 payload[2];
+	u8 nMinDataGap;
+	u8 plen;
+	int err;
+	u8 resp[5] = {0};
+	u8 resp_len = 5;
+	/*
+	 * must long enough for RECV_SW_DIR == 2;
+	 * need lss_dir at least 4 for GL9755 device
+	 * max compitable g_lss_dir = 0
+	 */
+	u32 g_lss_dir = 0;
+
+	DBG("SET_COMMON_CFG: write Generic Settings.\n");
+	header = UHS2_NATIVE_PACKET |
+		 UHS2_PACKET_TYPE_CCMD | host->uhs2_dev_prop.node_id;
+	arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_GEN_SET >> 8);
+
+	if (host->uhs2_dev_prop.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
+	    host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
+		/* Support HD */
+		DBG("Both Host and device support 2L-HD.\n");
+		host->flags |= MMC_UHS2_2L_HD;
+		host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
+		host->uhs2_dev_prop.n_lanes_set =
+				UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
+		nMinDataGap = 1;
+	} else {
+		/* Only support 2L-FD so far */
+		host->flags &= ~MMC_UHS2_2L_HD;
+		host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
+		host->uhs2_dev_prop.n_lanes_set =
+				UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
+		nMinDataGap = 3;
+	}
+
+	plen = 2;
+	payload[0] = host->uhs2_dev_prop.n_lanes_set <<
+		     UHS2_DEV_CONFIG_N_LANES_POS;
+	payload[1] = 0;
+	payload[0] = cpu_to_be32(payload[0]);
+	payload[1] = cpu_to_be32(payload[1]);
+
+	DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x\n", header, arg);
+	DBG("UHS2 write Generic Settings %08x %08x\n",
+	    payload[0], payload[1]);
+	DBG("flags=%08x dev_prop.n_lanes_set=%x host_caps.n_lanes_set=%x\n",
+	    host->flags,
+	    host->uhs2_dev_prop.n_lanes_set,
+	    host->uhs2_caps.n_lanes_set);
+
+	/*
+	 * There is no payload because per spec, there should be
+	 * no payload field for read CCMD.
+	 * Plen is set in arg. Per spec, plen for read CCMD
+	 * represents the len of read data which is assigned in payload
+	 * of following RES (p136).
+	 */
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	DBG("SET_COMMON_CFG: PHY Settings.\n");
+	arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_PHY_SET >> 8);
+
+	for (nTry = 0; nTry < 2; nTry++) {
+		plen = 2;
+
+		if (host->uhs2_caps.speed_range ==
+			UHS2_DEV_CONFIG_PHY_SET_SPEED_B) {
+			host->flags |= MMC_UHS2_SPEED_B;
+			host->uhs2_dev_prop.speed_range_set =
+				UHS2_DEV_CONFIG_PHY_SET_SPEED_B;
+			DBG("set dev_prop.speed_range_set to SPEED_B\n");
+		} else {
+			host->uhs2_dev_prop.speed_range_set =
+				UHS2_DEV_CONFIG_PHY_SET_SPEED_A;
+			host->flags &= ~MMC_UHS2_SPEED_B;
+			DBG("set dev_prop.speed_range_set to SPEED_A\n");
+		}
+
+		payload[0] = host->uhs2_dev_prop.speed_range_set <<
+				UHS2_DEV_CONFIG_PHY_SET_SPEED_POS;
+
+		host->uhs2_dev_prop.n_lss_sync_set =
+			(min(host->uhs2_dev_prop.n_lss_sync,
+			host->uhs2_caps.n_lss_sync) >> 2) &
+			UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
+		host->uhs2_caps.n_lss_sync_set =
+			host->uhs2_dev_prop.n_lss_sync_set;
+
+		if (nTry) {
+			host->uhs2_dev_prop.n_lss_dir_set =
+				(max(host->uhs2_dev_prop.n_lss_dir,
+				host->uhs2_caps.n_lss_dir) >> 3) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+			host->uhs2_caps.n_lss_dir_set =
+				host->uhs2_dev_prop.n_lss_dir_set;
+			payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
+				UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
+				host->uhs2_dev_prop.n_lss_sync_set;
+		} else {
+			host->uhs2_caps.n_lss_dir_set =
+				(host->uhs2_dev_prop.n_lss_dir >> 3) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+			host->uhs2_dev_prop.n_lss_dir_set =
+				((host->uhs2_caps.n_lss_dir >> 3) + 1) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+		}
+
+		if (!g_lss_dir) {
+			host->uhs2_dev_prop.n_lss_dir_set = 0;
+		} else {
+			host->uhs2_dev_prop.n_lss_dir_set =
+				max((u8)g_lss_dir,
+				    host->uhs2_dev_prop.n_lss_dir_set);
+		}
+
+		payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
+				UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
+				host->uhs2_dev_prop.n_lss_sync_set;
+		payload[0] = cpu_to_be32(payload[0]);
+		payload[1] = cpu_to_be32(payload[1]);
+
+		DBG("UHS2 SET PHY Settings  %08x %08x\n",
+		    payload[0], payload[1]);
+		DBG("host->flags=%08x dev_prop.speed_range_set=%x\n",
+		    host->flags,
+		    host->uhs2_dev_prop.speed_range_set);
+		DBG("dev_prop.n_lss_sync_set=%x host_caps.n_lss_sync_set=%x\n",
+		    host->uhs2_dev_prop.n_lss_sync_set,
+		    host->uhs2_caps.n_lss_sync_set);
+		DBG("dev_prop.n_lss_dir_set=%x host_caps.n_lss_dir_set=%x\n",
+		    host->uhs2_dev_prop.n_lss_dir_set,
+		    host->uhs2_caps.n_lss_dir_set);
+
+		DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n",
+		    header, arg);
+		DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n",
+		    payload[0], payload[1]);
+
+		resp_len = 4;
+		memset(resp, 0, sizeof(resp));
+
+		uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
+				  payload, plen, resp, resp_len);
+
+		err = mmc_wait_for_cmd(host, &cmd, 0);
+		if (err) {
+			pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+			       mmc_hostname(host), __func__, err);
+			return -EIO;
+		}
+
+		if (!(resp[2] & 0x80))
+			break;
+
+		DBG("%s: %s: UHS2 SET PHY Settings fail, res= 0x%x!\n",
+		    mmc_hostname(host), __func__,  resp[2]);
+	}
+
+	DBG("SET_COMMON_CFG: LINK-TRAN Settings.\n");
+	arg = ((UHS2_DEV_CONFIG_LINK_TRAN_SET & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_LINK_TRAN_SET >> 8);
+
+	plen = 2;
+
+	if (host->uhs2_dev_prop.app_type == UHS2_DEV_CONFIG_APP_SD_MEM)
+		host->uhs2_dev_prop.maxblk_len_set =
+			UHS2_DEV_CONFIG_LT_SET_MAX_BLK_LEN;
+	else
+		host->uhs2_dev_prop.maxblk_len_set =
+			min(host->uhs2_dev_prop.maxblk_len,
+			    host->uhs2_caps.maxblk_len);
+	host->uhs2_caps.maxblk_len_set = host->uhs2_dev_prop.maxblk_len_set;
+
+	host->uhs2_dev_prop.n_fcu_set =
+		min(host->uhs2_dev_prop.n_fcu,
+		    host->uhs2_caps.n_fcu);
+	host->uhs2_caps.n_fcu_set = host->uhs2_dev_prop.n_fcu_set;
+
+	host->uhs2_dev_prop.n_data_gap_set =
+		max(nMinDataGap, host->uhs2_dev_prop.n_data_gap);
+
+	host->uhs2_caps.n_data_gap_set = host->uhs2_dev_prop.n_data_gap_set;
+
+	host->uhs2_caps.max_retry_set = 3;
+	host->uhs2_dev_prop.max_retry_set = host->uhs2_caps.max_retry_set;
+
+	payload[0] = (host->uhs2_dev_prop.maxblk_len_set <<
+			UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) |
+			(host->uhs2_dev_prop.max_retry_set <<
+			UHS2_DEV_CONFIG_LT_SET_MAX_RETRY_POS) |
+			(host->uhs2_dev_prop.n_fcu_set <<
+			UHS2_DEV_CONFIG_N_FCU_POS);
+	payload[1] = host->uhs2_dev_prop.n_data_gap_set;
+	payload[0] = cpu_to_be32(payload[0]);
+	payload[1] = cpu_to_be32(payload[1]);
+
+	DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n", header, arg);
+	DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n", payload[0], payload[1]);
+
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	DBG("SET_COMMON_CFG: Set Config Completion.\n");
+	arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_GEN_SET >> 8);
+
+	plen = 2;
+	payload[0] = 0;
+	payload[1] = UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE;
+	payload[0] = cpu_to_be32(payload[0]);
+	payload[1] = cpu_to_be32(payload[1]);
+
+	DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x, payload[0] = 0x%x.\n",
+	    header, arg, payload[0]);
+	resp_len = 5;
+	memset(resp, 0, sizeof(resp));
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  resp, resp_len);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	/* Set host Config Setting registers */
+	if (host->ops->uhs2_set_reg(host, SET_CONFIG)) {
+		pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int uhs2_go_dormant(struct mmc_host *host, bool hibernate)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 payload[1];
+	u8 plen = 1;
+	int err;
+
+	/* Disable Normal INT */
+	if (host->ops->uhs2_set_reg(host, DISABLE_INT)) {
+		pr_err("%s: %s: UHS2 DISABLE_INT fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
+		host->uhs2_dev_prop.node_id;
+
+	arg = ((UHS2_DEV_CMD_GO_DORMANT_STATE & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_4B |
+		(UHS2_DEV_CMD_GO_DORMANT_STATE >> 8);
+
+	if (hibernate)
+		payload[0] = UHS2_DEV_CMD_DORMANT_HIBER;
+
+	DBG("Begin GO_DORMANT_STATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
+	    header, arg, payload[0]);
+	uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	/* Check Dormant State in Present */
+	if (host->ops->uhs2_set_reg(host, CHECK_DORMANT)) {
+		pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	host->ops->uhs2_disable_clk(host);
+
+	return 0;
+}
+
+static int uhs2_change_speed(struct mmc_host *host)
+{
+	int err;
+
+	/* Change Speed Range */
+	if (host->ops->uhs2_set_reg(host, SET_SPEED_B)) {
+		pr_err("%s: %s: UHS2 SET_SPEED fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	err = uhs2_go_dormant(host, false);
+	if (err) {
+		pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	/* restore sd clock */
+	mdelay(5);
+	host->ops->uhs2_enable_clk(host);
+
+	/* Enable Normal INT */
+	if (host->ops->uhs2_set_reg(host, ENABLE_INT)) {
+		pr_err("%s: %s: UHS2 ENABLE_INT fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	if (host->ops->uhs2_detect_init(host)) {
+		pr_err("%s: %s: uhs2_detect_init() fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * mmc_uhs2_rescan_try_freq - select UHS2 interface
+ * @host: MMC host
+ * @freq: Bus speed
+ *
+ * Try to select UHS2 interface and initialize the bus for a given
+ * frequency, @freq.
+ *
+ * Return:	0 on success, non-zero error on failure
+ */
+int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq)
+{
+	int err = -EIO;
+
+	host->flags |= MMC_UHS2_SUPPORT;
+	host->f_init = freq;
+
+	pr_debug("%s: %s: trying to init card at %u Hz\n",
+		 mmc_hostname(host), __func__, host->f_init);
+
+	mmc_power_up(host, 0);
+	if (host->ops->uhs2_detect_init(host)) {
+		pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
+		err = UHS2_PHY_INIT_ERR;
+		goto init_fail;
+	}
+
+	if (uhs2_dev_init(host)) {
+		pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
+		goto init_fail;
+	}
+
+	if (uhs2_enum(host)) {
+		pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
+		goto init_fail;
+	}
+
+	if (uhs2_config_read(host)) {
+		pr_err("%s: UHS2 INQUIRY_CONFIG fail!\n", mmc_hostname(host));
+		goto init_fail;
+	}
+
+	if (uhs2_config_write(host)) {
+		pr_err("%s: UHS2 SET_COMMON_CONFIG fail!\n",
+		       mmc_hostname(host));
+		goto init_fail;
+	}
+
+	mmc_delay(10);
+
+	/* Change to Speed Range B if it is supported */
+	if (host->flags & MMC_UHS2_SPEED_B)
+		if (uhs2_change_speed(host)) {
+			pr_err("%s: UHS2 uhs2_change_speed() fail!\n",
+			       mmc_hostname(host));
+			goto init_fail;
+		}
+
+	host->flags |= MMC_UHS2_INITIALIZED;
+
+	mmc_send_if_cond(host, host->ocr_avail);
+
+	/* On market, only can some SD cards support UHS-II so only call SD
+	 * attach process here.
+	 */
+	if (!(host->caps2 & MMC_CAP2_NO_SD)) {
+		err = mmc_attach_sd(host);
+		if (!err)
+			return 0;
+	} else {
+		err = -EIO;
+	}
+
+init_fail:
+	mmc_power_off(host);
+	if (host->flags & MMC_UHS2_INITIALIZED)
+		host->flags &= ~MMC_UHS2_INITIALIZED;
+	host->flags &= ~MMC_UHS2_SUPPORT;
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(mmc_uhs2_rescan_try_freq);
diff --git a/drivers/mmc/core/uhs2.h b/drivers/mmc/core/uhs2.h
new file mode 100644
index 000000000000..e3389d4dda3b
--- /dev/null
+++ b/drivers/mmc/core/uhs2.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  driver/mmc/core/uhs2.h - UHS-II driver
+ *
+ * Header file for UHS-II packets, Host Controller registers and I/O
+ * accessors.
+ *
+ *  Copyright (C) 2014 Intel Corp, All Rights Reserved.
+ */
+#ifndef MMC_UHS2_H
+#define MMC_UHS2_H
+
+#include <linux/mmc/core.h>
+#include <linux/mmc/host.h>
+
+#define UHS2_PHY_INIT_ERR	1
+
+int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq);
+
+#endif /* MMC_UHS2_H */
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface
  2020-07-10 11:08 [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface Ben Chuang
@ 2020-08-18 11:41 ` Ulf Hansson
  2020-08-21 11:33   ` Ben Chuang
  0 siblings, 1 reply; 5+ messages in thread
From: Ulf Hansson @ 2020-08-18 11:41 UTC (permalink / raw)
  To: Ben Chuang
  Cc: Adrian Hunter, linux-mmc, Linux Kernel Mailing List, Ben Chuang,
	Takahiro Akashi, greg.tu

On Fri, 10 Jul 2020 at 13:08, Ben Chuang <benchuanggli@gmail.com> wrote:
>
> From: Ben Chuang <ben.chuang@genesyslogic.com.tw>
>
> The flow of "interface selection and initialization" was a bit modified
> for UHS-II card. This commit follows the sequence defined in SD
> specification (Part 1).
> See section 7.2.3 in "UHS-II Simplified Addendum."
>
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
>  drivers/mmc/core/Makefile |   2 +-
>  drivers/mmc/core/bus.c    |   5 +-
>  drivers/mmc/core/core.c   |  33 +-
>  drivers/mmc/core/sd.c     |  26 ++
>  drivers/mmc/core/uhs2.c   | 800 ++++++++++++++++++++++++++++++++++++++
>  drivers/mmc/core/uhs2.h   |  20 +
>  6 files changed, 882 insertions(+), 4 deletions(-)
>  create mode 100644 drivers/mmc/core/uhs2.c
>  create mode 100644 drivers/mmc/core/uhs2.h
>
> diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
> index 95ffe008ebdf..e2a90dc98afc 100644
> --- a/drivers/mmc/core/Makefile
> +++ b/drivers/mmc/core/Makefile
> @@ -8,7 +8,7 @@ mmc_core-y                      := core.o bus.o host.o \
>                                    mmc.o mmc_ops.o sd.o sd_ops.o \
>                                    sdio.o sdio_ops.o sdio_bus.o \
>                                    sdio_cis.o sdio_io.o sdio_irq.o \
> -                                  slot-gpio.o regulator.o
> +                                  slot-gpio.o regulator.o uhs2.o
>  mmc_core-$(CONFIG_OF)          += pwrseq.o
>  obj-$(CONFIG_PWRSEQ_SIMPLE)    += pwrseq_simple.o
>  obj-$(CONFIG_PWRSEQ_SD8787)    += pwrseq_sd8787.o
> diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
> index 70207f11a654..66d3e942f3fc 100644
> --- a/drivers/mmc/core/bus.c
> +++ b/drivers/mmc/core/bus.c
> @@ -350,8 +350,9 @@ int mmc_add_card(struct mmc_card *card)
>         } else {
>                 pr_info("%s: new %s%s%s%s%s%s card at address %04x\n",
>                         mmc_hostname(card->host),
> -                       mmc_card_uhs(card) ? "ultra high speed " :
> -                       (mmc_card_hs(card) ? "high speed " : ""),
> +                       mmc_card_uhs2(card) ? "ultra high speed 2 " :
> +                       (mmc_card_uhs(card) ? "ultra high speed 1 " :

Perhaps use "UHS-I" and "UHS-II" instead.

> +                       (mmc_card_hs(card) ? "high speed " : "")),
>                         mmc_card_hs400(card) ? "HS400 " :
>                         (mmc_card_hs200(card) ? "HS200 " : ""),
>                         mmc_card_hs400es(card) ? "Enhanced strobe " : "",
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index c6540d56646b..e2534f3446ce 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -31,6 +31,7 @@
>  #include <linux/mmc/mmc.h>
>  #include <linux/mmc/sd.h>
>  #include <linux/mmc/slot-gpio.h>
> +#include <linux/mmc/uhs2.h>
>
>  #define CREATE_TRACE_POINTS
>  #include <trace/events/mmc.h>
> @@ -41,6 +42,7 @@
>  #include "host.h"
>  #include "sdio_bus.h"
>  #include "pwrseq.h"
> +#include "uhs2.h"
>
>  #include "mmc_ops.h"
>  #include "sd_ops.h"
> @@ -51,6 +53,7 @@
>  #define SD_DISCARD_TIMEOUT_MS  (250)
>
>  static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> +static const unsigned int uhs2_freqs[] = { 52000000, 26000000 };
>
>  /*
>   * Enabling software CRCs on the data blocks can be a significant (30%)
> @@ -2165,9 +2168,10 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
>                 if (!mmc_attach_sdio(host))
>                         return 0;
>
> -       if (!(host->caps2 & MMC_CAP2_NO_SD))
> +       if (!(host->caps2 & MMC_CAP2_NO_SD)) {
>                 if (!mmc_attach_sd(host))
>                         return 0;
> +       }
>
>         if (!(host->caps2 & MMC_CAP2_NO_MMC))
>                 if (!mmc_attach_mmc(host))
> @@ -2300,6 +2304,33 @@ void mmc_rescan(struct work_struct *work)
>                 goto out;
>         }
>
> +       if (host->caps & MMC_CAP_UHS2) {
> +               /*
> +                * Start to try UHS-II initialization from 52MHz to 26MHz
> +                * (RCLK range) per spec.
> +                */
> +               for (i = 0; i < ARRAY_SIZE(uhs2_freqs); i++) {
> +                       unsigned int freq = uhs2_freqs[i];
> +                       int err;
> +
> +                       err = mmc_uhs2_rescan_try_freq(host,
> +                                                      max(freq, host->f_min));
> +                       if (!err) {
> +                               mmc_release_host(host);
> +                               goto out;
> +                       }
> +
> +                       if (err == UHS2_PHY_INIT_ERR)
> +                               /* UHS2 IF detect or Lane Sync error.
> +                                * Try legacy interface.
> +                                */
> +                               break;
> +
> +                       if (freq <= host->f_min)
> +                               break;
> +               }

Assuming we change the initialization order, trying to initialize the
legacy SD interface first to figure out if UHS-II is supported, then I
think we should be able to move the entire code above into a the
UHS-II specific code/path.

> +       }
> +
>         for (i = 0; i < ARRAY_SIZE(freqs); i++) {
>                 unsigned int freq = freqs[i];
>                 if (freq > host->f_max) {
> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> index 5a2210c25aa7..c5b071bd98b3 100644
> --- a/drivers/mmc/core/sd.c
> +++ b/drivers/mmc/core/sd.c
> @@ -901,6 +901,20 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
>                 err = mmc_read_switch(card);
>                 if (err)
>                         return err;
> +               if (host->flags & MMC_UHS2_INITIALIZED) {

Rather than using host->flags, to tweak the behavior of
mmc_sd_setup_card() to support UHS-II, I would prefer to give
mmc_sd_setup_card() a new in-parameter that it can look at instead.

> +                       u8 status[64];
> +                       /*
> +                        * send CMD6 to set Maximum Power Consumption
> +                        * to get better performance
> +                        */
> +                       err = mmc_sd_switch(card, 0, 3,
> +                                           SD_SET_CURRENT_LIMIT_1000, status);
> +                       if (!err) {
> +                               err = mmc_sd_switch(card, 1, 3,
> +                                                   SD_SET_CURRENT_LIMIT_1000,
> +                                                   status);
> +                       }
> +               }
>         }
>
>         /*
> @@ -1043,6 +1057,11 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
>         if (err)
>                 goto free_card;
>
> +       /* For UHS2, skip the UHS-I initialization. */
> +       if ((host->flags & MMC_UHS2_SUPPORT) &&
> +           (host->flags & MMC_UHS2_INITIALIZED))
> +               goto done;

mmc_sd_init_card() is also called at system resume, to re-initialize the card.

Re-initialization is going to be needed for UHS-II cards as well,
since we should ideally avoid wasting energy in system suspend state
for these cards as well.

Perhaps you haven't looked at that part yet? Or I may be missing something here?

> +
>         /*
>          * If the card has not been power cycled, it may still be using 1.8V
>          * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
> @@ -1334,6 +1353,13 @@ int mmc_attach_sd(struct mmc_host *host)
>
>         rocr = mmc_select_voltage(host, ocr);
>
> +       /*
> +        * Some cards have zero value of rocr in UHS-II mode. Assign host's ocr
> +        * value to rocr.
> +        */
> +       if ((host->flags & MMC_UHS2_INITIALIZED) && !rocr)
> +               rocr = host->ocr_avail;

As stated already earlier above, we should probably be able to move
any UHS-II specific bits to the UHS-II code/path.

> +
>         /*
>          * Can we support the voltage(s) of the card(s)?
>          */
> diff --git a/drivers/mmc/core/uhs2.c b/drivers/mmc/core/uhs2.c
> new file mode 100644
> index 000000000000..a3b20ac6f315
> --- /dev/null
> +++ b/drivers/mmc/core/uhs2.c
> @@ -0,0 +1,800 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + *  linux/drivers/mmc/core/uhs2.c - UHS-II driver
> + *
> + *  Copyright (C) 2014 Intel Corp, All Rights Reserved.
> + *  Copyright (C) 2020 Genesys Logic, Inc.
> + *  Authors: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> + *  Copyright (C) 2020 Linaro Limited
> + *  Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
> + */
> +
> +#include <asm/byteorder.h>
> +#include <linux/err.h>
> +#include <linux/slab.h>
> +
> +#include <linux/mmc/host.h>
> +#include <linux/mmc/card.h>
> +#include <linux/mmc/mmc.h>
> +#include <linux/mmc/core.h>
> +#include <linux/mmc/sdio.h>
> +#include <linux/mmc/slot-gpio.h>
> +#include <linux/mmc/uhs2.h>
> +
> +#include "uhs2.h"
> +#include "mmc_ops.h"
> +#include "sd_ops.h"
> +#include "core.h"
> +
> +#define DBG(f, x...) \
> +       pr_warn("[%s()]: " f, __func__, ## x)
> +
> +/**
> + * uhs2_cmd_assemble - assemble and build up uhs2 command
> + * @cmd:       MMC command
> + * @uhs2_cmd:  UHS2 command
> + * @header:    Value of packet header
> + * @arg:       Argument of packet
> + * @payload:   Payload of packet
> + * @plen:      Payload length
> + * @resp:      Buffer for response
> + * @resp_len:  Response buffer length
> + *
> + * resp is inputted outside which should be a variable created by caller
> + * so caller should handle it. For SD command, there is no uhs2_resp and
> + * response should be stored in resp of mmc_command.
> + */
> +static void uhs2_cmd_assemble(struct mmc_command *cmd,
> +                             struct uhs2_command *uhs2_cmd,
> +                             u16 header, u16 arg,
> +                             u32 *payload, u8 plen, u8 *resp, u8 resp_len)
> +{
> +       uhs2_cmd->header = header;
> +       uhs2_cmd->arg = arg;
> +       uhs2_cmd->payload = payload;
> +       uhs2_cmd->payload_len = plen * sizeof(u32);
> +       uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
> +
> +       cmd->uhs2_cmd = uhs2_cmd;
> +       cmd->uhs2_resp = resp;
> +       cmd->uhs2_resp_len = resp_len;
> +
> +       pr_debug("%s: uhs2_cmd: header=0x%x arg=0x%x\n",
> +                __func__, uhs2_cmd->header, uhs2_cmd->arg);
> +       pr_debug("%s:           payload_len=%d packet_len=%d resp_len=%d\n",
> +                __func__, uhs2_cmd->payload_len, uhs2_cmd->packet_len,
> +               cmd->uhs2_resp_len);

I noticed that there is lots of debug code around. I understand that
it's useful during development, but I think we should be able to
remove some of it. Can you please have a look and clean up that?

> +}
> +
> +static int uhs2_dev_init(struct mmc_host *host)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u32 cnt;
> +       u32 dap, gap, gap1;
> +       u16 header = 0, arg = 0;
> +       u32 payload[1];
> +       u8 plen = 1;
> +       u8 gd = 0, cf = 1;
> +       u8 resp[6] = {0};
> +       u8 resp_len = 6;
> +       int err;
> +
> +       dap = host->uhs2_caps.dap;
> +       gap = host->uhs2_caps.gap;
> +
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> +       arg = ((UHS2_DEV_CMD_DEVICE_INIT & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_4B |
> +               (UHS2_DEV_CMD_DEVICE_INIT >> 8);
> +
> +       /* need this for some cards */
> +       cmd.busy_timeout = 1000;

Is this according to spec? Please add defines for timeout values.

> +
> +       for (cnt = 0; cnt < 30; cnt++) {
> +               payload[0] = ((dap & 0xF) << 12) |
> +                       (cf << 11) |
> +                       ((gd & 0xF) << 4) |
> +                       (gap & 0xF);
> +
> +               uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> +                                 payload, plen, resp, resp_len);
> +
> +               DBG("Begin DEVICE_INIT, header=0x%x, arg=0x%x, payload=0x%x.\n",
> +                   header, arg, payload[0]);
> +
> +               DBG("Sending DEVICE_INIT. Count = %d\n", cnt);
> +               err = mmc_wait_for_cmd(host, &cmd, 0);

Debug code, please clean this up...

> +
> +               if (err) {
> +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                              mmc_hostname(host), __func__, err);
> +                       return -EIO;
> +               }
> +
> +               if (IS_ENABLED(CONFIG_MMC_DEBUG)) {

Debug code, please clean this up. I am stopping from commenting on
that, as stated, please have a look at all the code to clean this up.

> +                       int i;
> +
> +                       pr_warn("%s: DEVICE_INIT response is: ",
> +                               mmc_hostname(host));
> +                       for (i = 0; i < resp_len; i++)
> +                               pr_warn("0x%x ", resp[i]);
> +                       pr_warn("\n");
> +               }
> +
> +               if (resp[3] != (UHS2_DEV_CMD_DEVICE_INIT & 0xFF)) {
> +                       pr_err("%s: DEVICE_INIT response is wrong!\n",
> +                              mmc_hostname(host));
> +                       return -EIO;
> +               }
> +
> +               if (resp[5] & 0x8) {
> +                       DBG("CF is set, device is initialized!\n");
> +                       host->group_desc = gd;
> +                       break;
> +               }
> +               gap1 = resp[4] & 0x0F;
> +               if (gap == gap1)
> +                       gd++;
> +       }
> +       if (cnt == 30) {
> +               pr_err("%s: DEVICE_INIT fail, already 30 times!\n",
> +                      mmc_hostname(host));
> +               return -EIO;
> +       }
> +
> +       return 0;
> +}
> +
> +static int uhs2_enum(struct mmc_host *host)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 payload[1];
> +       u8 plen = 1;
> +       u8 id_f = 0xF, id_l = 0x0;
> +       u8 resp[8] = {0};
> +       u8 resp_len = 8;
> +       int err;
> +
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> +       arg = ((UHS2_DEV_CMD_ENUMERATE & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_4B |
> +               (UHS2_DEV_CMD_ENUMERATE >> 8);
> +
> +       payload[0] = (id_f << 4) | id_l;
> +
> +       DBG("Begin ENUMERATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
> +           header, arg, payload[0]);
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         resp, resp_len);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> +               int i;
> +
> +               pr_warn("%s: ENUMERATE response is: ", mmc_hostname(host));
> +               for (i = 0; i < resp_len; i++)
> +                       pr_warn("0x%x ", resp[i]);
> +               pr_warn("\n");
> +       }
> +
> +       if (resp[3] != (UHS2_DEV_CMD_ENUMERATE & 0xFF)) {
> +               pr_err("%s: ENUMERATE response is wrong!\n",
> +                      mmc_hostname(host));
> +               return -EIO;
> +       }
> +
> +       id_f = (resp[4] >> 4) & 0xF;
> +       id_l = resp[4] & 0xF;
> +       DBG("id_f = %d, id_l = %d.\n", id_f, id_l);
> +       DBG("Enumerate Cmd Completed. No. of Devices connected = %d\n",
> +           id_l - id_f + 1);
> +       host->uhs2_dev_prop.node_id = id_f;
> +
> +       return 0;
> +}
> +
> +static int uhs2_config_read(struct mmc_host *host)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 cap;
> +       int err;
> +
> +       DBG("INQUIRY_CFG: read Generic Caps.\n");
> +       header = UHS2_NATIVE_PACKET |
> +                UHS2_PACKET_TYPE_CCMD |
> +                host->uhs2_dev_prop.node_id;
> +       arg = ((UHS2_DEV_CONFIG_GEN_CAPS & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_READ |
> +               UHS2_NATIVE_CMD_PLEN_4B |
> +               (UHS2_DEV_CONFIG_GEN_CAPS >> 8);
> +
> +       DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> +           header, arg);
> +       /* There is no payload because per spec, there should be
> +        * no payload field for read CCMD.
> +        * Plen is set in arg. Per spec, plen for read CCMD
> +        * represents the len of read data which is assigned in payload
> +        * of following RES (p136).
> +        */
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> +               int i;
> +
> +               pr_warn("%s: INQUIRY_CFG generic response is: ",
> +                       mmc_hostname(host));
> +               for (i = 0; i < 2; i++)
> +                       pr_warn("0x%x ", cmd.resp[i]);
> +               pr_warn("\n");
> +       }
> +
> +       cap = cmd.resp[0];
> +       DBG("Device Generic Caps (0-31) is: 0x%x.\n", cap);
> +       host->uhs2_dev_prop.n_lanes = (cap >> UHS2_DEV_CONFIG_N_LANES_POS) &
> +                                       UHS2_DEV_CONFIG_N_LANES_MASK;
> +       host->uhs2_dev_prop.dadr_len = (cap >> UHS2_DEV_CONFIG_DADR_POS) &
> +                                       UHS2_DEV_CONFIG_DADR_MASK;
> +       host->uhs2_dev_prop.app_type = (cap >> UHS2_DEV_CONFIG_APP_POS) &
> +                                       UHS2_DEV_CONFIG_APP_MASK;
> +
> +       DBG("INQUIRY_CFG: read PHY Caps.\n");
> +       arg = ((UHS2_DEV_CONFIG_PHY_CAPS & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_READ |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_PHY_CAPS >> 8);
> +
> +       DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> +           header, arg);
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> +               int i;
> +
> +               pr_warn("%s: INQUIRY_CFG PHY response is: ",
> +                       mmc_hostname(host));
> +               for (i = 0; i < 2; i++)
> +                       pr_warn("0x%x ", cmd.resp[i]);
> +               pr_warn("\n");
> +       }
> +
> +       cap = cmd.resp[0];
> +       DBG("Device PHY Caps (0-31) is: 0x%x.\n", cap);
> +       host->uhs2_dev_prop.phy_minor_rev = cap &
> +                                       UHS2_DEV_CONFIG_PHY_MINOR_MASK;
> +       host->uhs2_dev_prop.phy_major_rev = (cap >>
> +                                       UHS2_DEV_CONFIG_PHY_MAJOR_POS) &
> +                                       UHS2_DEV_CONFIG_PHY_MAJOR_MASK;
> +       host->uhs2_dev_prop.can_hibernate = (cap >>
> +                                       UHS2_DEV_CONFIG_CAN_HIBER_POS) &
> +                                       UHS2_DEV_CONFIG_CAN_HIBER_MASK;
> +
> +       cap = cmd.resp[1];
> +       DBG("Device PHY Caps (32-63) is: 0x%x.\n", cap);
> +       host->uhs2_dev_prop.n_lss_sync = cap & UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> +       host->uhs2_dev_prop.n_lss_dir = (cap >>
> +                                       UHS2_DEV_CONFIG_N_LSS_DIR_POS) &
> +                                       UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +       if (host->uhs2_dev_prop.n_lss_sync == 0)
> +               host->uhs2_dev_prop.n_lss_sync = 16 << 2;
> +       else
> +               host->uhs2_dev_prop.n_lss_sync <<= 2;
> +
> +       if (host->uhs2_dev_prop.n_lss_dir == 0)
> +               host->uhs2_dev_prop.n_lss_dir = 16 << 3;
> +       else
> +               host->uhs2_dev_prop.n_lss_dir <<= 3;
> +
> +       DBG("INQUIRY_CFG: read LINK-TRAN Caps.\n");
> +       arg = ((UHS2_DEV_CONFIG_LINK_TRAN_CAPS & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_READ |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_LINK_TRAN_CAPS >> 8);
> +
> +       DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> +           header, arg);
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> +               int i;
> +
> +               pr_warn("%s: INQUIRY_CFG Link-Tran response is: ",
> +                       mmc_hostname(host));
> +               for (i = 0; i < 2; i++)
> +                       pr_warn("0x%x ", cmd.resp[i]);
> +               pr_warn("\n");
> +       }
> +
> +       cap = cmd.resp[0];
> +       DBG("Device LINK-TRAN Caps (0-31) is: 0x%x.\n", cap);
> +       host->uhs2_dev_prop.link_minor_rev = cap &
> +                                       UHS2_DEV_CONFIG_LT_MINOR_MASK;
> +       host->uhs2_dev_prop.link_major_rev = (cap >>
> +                                       UHS2_DEV_CONFIG_LT_MAJOR_POS) &
> +                                       UHS2_DEV_CONFIG_LT_MAJOR_MASK;
> +       host->uhs2_dev_prop.n_fcu = (cap >> UHS2_DEV_CONFIG_N_FCU_POS) &
> +                                       UHS2_DEV_CONFIG_N_FCU_MASK;
> +       host->uhs2_dev_prop.dev_type = (cap >> UHS2_DEV_CONFIG_DEV_TYPE_POS) &
> +                                       UHS2_DEV_CONFIG_DEV_TYPE_MASK;
> +       host->uhs2_dev_prop.maxblk_len = (cap >>
> +                                       UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) &
> +                                       UHS2_DEV_CONFIG_MAX_BLK_LEN_MASK;
> +
> +       cap = cmd.resp[1];
> +       DBG("Device LINK-TRAN Caps (32-63) is: 0x%x.\n", cap);
> +       host->uhs2_dev_prop.n_data_gap = cap & UHS2_DEV_CONFIG_N_DATA_GAP_MASK;
> +       if (host->uhs2_dev_prop.n_fcu == 0)
> +               host->uhs2_dev_prop.n_fcu = 256;
> +
> +       return 0;
> +}
> +
> +static int uhs2_config_write(struct mmc_host *host)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 nTry;
> +       u32 payload[2];
> +       u8 nMinDataGap;
> +       u8 plen;
> +       int err;
> +       u8 resp[5] = {0};
> +       u8 resp_len = 5;
> +       /*
> +        * must long enough for RECV_SW_DIR == 2;
> +        * need lss_dir at least 4 for GL9755 device
> +        * max compitable g_lss_dir = 0
> +        */
> +       u32 g_lss_dir = 0;
> +
> +       DBG("SET_COMMON_CFG: write Generic Settings.\n");
> +       header = UHS2_NATIVE_PACKET |
> +                UHS2_PACKET_TYPE_CCMD | host->uhs2_dev_prop.node_id;
> +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_GEN_SET >> 8);
> +
> +       if (host->uhs2_dev_prop.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
> +           host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
> +               /* Support HD */
> +               DBG("Both Host and device support 2L-HD.\n");
> +               host->flags |= MMC_UHS2_2L_HD;
> +               host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> +               host->uhs2_dev_prop.n_lanes_set =
> +                               UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> +               nMinDataGap = 1;
> +       } else {
> +               /* Only support 2L-FD so far */
> +               host->flags &= ~MMC_UHS2_2L_HD;
> +               host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> +               host->uhs2_dev_prop.n_lanes_set =
> +                               UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> +               nMinDataGap = 3;
> +       }
> +
> +       plen = 2;
> +       payload[0] = host->uhs2_dev_prop.n_lanes_set <<
> +                    UHS2_DEV_CONFIG_N_LANES_POS;
> +       payload[1] = 0;
> +       payload[0] = cpu_to_be32(payload[0]);
> +       payload[1] = cpu_to_be32(payload[1]);
> +
> +       DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x\n", header, arg);
> +       DBG("UHS2 write Generic Settings %08x %08x\n",
> +           payload[0], payload[1]);
> +       DBG("flags=%08x dev_prop.n_lanes_set=%x host_caps.n_lanes_set=%x\n",
> +           host->flags,
> +           host->uhs2_dev_prop.n_lanes_set,
> +           host->uhs2_caps.n_lanes_set);
> +
> +       /*
> +        * There is no payload because per spec, there should be
> +        * no payload field for read CCMD.
> +        * Plen is set in arg. Per spec, plen for read CCMD
> +        * represents the len of read data which is assigned in payload
> +        * of following RES (p136).
> +        */
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       DBG("SET_COMMON_CFG: PHY Settings.\n");
> +       arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_PHY_SET >> 8);
> +
> +       for (nTry = 0; nTry < 2; nTry++) {
> +               plen = 2;
> +
> +               if (host->uhs2_caps.speed_range ==
> +                       UHS2_DEV_CONFIG_PHY_SET_SPEED_B) {
> +                       host->flags |= MMC_UHS2_SPEED_B;
> +                       host->uhs2_dev_prop.speed_range_set =
> +                               UHS2_DEV_CONFIG_PHY_SET_SPEED_B;
> +                       DBG("set dev_prop.speed_range_set to SPEED_B\n");
> +               } else {
> +                       host->uhs2_dev_prop.speed_range_set =
> +                               UHS2_DEV_CONFIG_PHY_SET_SPEED_A;
> +                       host->flags &= ~MMC_UHS2_SPEED_B;
> +                       DBG("set dev_prop.speed_range_set to SPEED_A\n");
> +               }
> +
> +               payload[0] = host->uhs2_dev_prop.speed_range_set <<
> +                               UHS2_DEV_CONFIG_PHY_SET_SPEED_POS;
> +
> +               host->uhs2_dev_prop.n_lss_sync_set =
> +                       (min(host->uhs2_dev_prop.n_lss_sync,
> +                       host->uhs2_caps.n_lss_sync) >> 2) &
> +                       UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> +               host->uhs2_caps.n_lss_sync_set =
> +                       host->uhs2_dev_prop.n_lss_sync_set;
> +
> +               if (nTry) {
> +                       host->uhs2_dev_prop.n_lss_dir_set =
> +                               (max(host->uhs2_dev_prop.n_lss_dir,
> +                               host->uhs2_caps.n_lss_dir) >> 3) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +                       host->uhs2_caps.n_lss_dir_set =
> +                               host->uhs2_dev_prop.n_lss_dir_set;
> +                       payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> +                               host->uhs2_dev_prop.n_lss_sync_set;
> +               } else {
> +                       host->uhs2_caps.n_lss_dir_set =
> +                               (host->uhs2_dev_prop.n_lss_dir >> 3) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +                       host->uhs2_dev_prop.n_lss_dir_set =
> +                               ((host->uhs2_caps.n_lss_dir >> 3) + 1) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +               }
> +
> +               if (!g_lss_dir) {
> +                       host->uhs2_dev_prop.n_lss_dir_set = 0;
> +               } else {
> +                       host->uhs2_dev_prop.n_lss_dir_set =
> +                               max((u8)g_lss_dir,
> +                                   host->uhs2_dev_prop.n_lss_dir_set);
> +               }
> +
> +               payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> +                               host->uhs2_dev_prop.n_lss_sync_set;
> +               payload[0] = cpu_to_be32(payload[0]);
> +               payload[1] = cpu_to_be32(payload[1]);
> +
> +               DBG("UHS2 SET PHY Settings  %08x %08x\n",
> +                   payload[0], payload[1]);
> +               DBG("host->flags=%08x dev_prop.speed_range_set=%x\n",
> +                   host->flags,
> +                   host->uhs2_dev_prop.speed_range_set);
> +               DBG("dev_prop.n_lss_sync_set=%x host_caps.n_lss_sync_set=%x\n",
> +                   host->uhs2_dev_prop.n_lss_sync_set,
> +                   host->uhs2_caps.n_lss_sync_set);
> +               DBG("dev_prop.n_lss_dir_set=%x host_caps.n_lss_dir_set=%x\n",
> +                   host->uhs2_dev_prop.n_lss_dir_set,
> +                   host->uhs2_caps.n_lss_dir_set);
> +
> +               DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n",
> +                   header, arg);
> +               DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n",
> +                   payload[0], payload[1]);
> +
> +               resp_len = 4;
> +               memset(resp, 0, sizeof(resp));
> +
> +               uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> +                                 payload, plen, resp, resp_len);
> +
> +               err = mmc_wait_for_cmd(host, &cmd, 0);
> +               if (err) {
> +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                              mmc_hostname(host), __func__, err);
> +                       return -EIO;
> +               }
> +
> +               if (!(resp[2] & 0x80))
> +                       break;
> +
> +               DBG("%s: %s: UHS2 SET PHY Settings fail, res= 0x%x!\n",
> +                   mmc_hostname(host), __func__,  resp[2]);
> +       }
> +
> +       DBG("SET_COMMON_CFG: LINK-TRAN Settings.\n");
> +       arg = ((UHS2_DEV_CONFIG_LINK_TRAN_SET & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_LINK_TRAN_SET >> 8);
> +
> +       plen = 2;
> +
> +       if (host->uhs2_dev_prop.app_type == UHS2_DEV_CONFIG_APP_SD_MEM)
> +               host->uhs2_dev_prop.maxblk_len_set =
> +                       UHS2_DEV_CONFIG_LT_SET_MAX_BLK_LEN;
> +       else
> +               host->uhs2_dev_prop.maxblk_len_set =
> +                       min(host->uhs2_dev_prop.maxblk_len,
> +                           host->uhs2_caps.maxblk_len);
> +       host->uhs2_caps.maxblk_len_set = host->uhs2_dev_prop.maxblk_len_set;
> +
> +       host->uhs2_dev_prop.n_fcu_set =
> +               min(host->uhs2_dev_prop.n_fcu,
> +                   host->uhs2_caps.n_fcu);
> +       host->uhs2_caps.n_fcu_set = host->uhs2_dev_prop.n_fcu_set;
> +
> +       host->uhs2_dev_prop.n_data_gap_set =
> +               max(nMinDataGap, host->uhs2_dev_prop.n_data_gap);
> +
> +       host->uhs2_caps.n_data_gap_set = host->uhs2_dev_prop.n_data_gap_set;
> +
> +       host->uhs2_caps.max_retry_set = 3;
> +       host->uhs2_dev_prop.max_retry_set = host->uhs2_caps.max_retry_set;
> +
> +       payload[0] = (host->uhs2_dev_prop.maxblk_len_set <<
> +                       UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) |
> +                       (host->uhs2_dev_prop.max_retry_set <<
> +                       UHS2_DEV_CONFIG_LT_SET_MAX_RETRY_POS) |
> +                       (host->uhs2_dev_prop.n_fcu_set <<
> +                       UHS2_DEV_CONFIG_N_FCU_POS);
> +       payload[1] = host->uhs2_dev_prop.n_data_gap_set;
> +       payload[0] = cpu_to_be32(payload[0]);
> +       payload[1] = cpu_to_be32(payload[1]);
> +
> +       DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n", header, arg);
> +       DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n", payload[0], payload[1]);
> +
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       DBG("SET_COMMON_CFG: Set Config Completion.\n");
> +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_GEN_SET >> 8);
> +
> +       plen = 2;
> +       payload[0] = 0;
> +       payload[1] = UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE;
> +       payload[0] = cpu_to_be32(payload[0]);
> +       payload[1] = cpu_to_be32(payload[1]);
> +
> +       DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x, payload[0] = 0x%x.\n",
> +           header, arg, payload[0]);
> +       resp_len = 5;
> +       memset(resp, 0, sizeof(resp));
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         resp, resp_len);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       /* Set host Config Setting registers */
> +       if (host->ops->uhs2_set_reg(host, SET_CONFIG)) {
> +               pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       return 0;
> +}
> +
> +static int uhs2_go_dormant(struct mmc_host *host, bool hibernate)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 payload[1];
> +       u8 plen = 1;
> +       int err;
> +
> +       /* Disable Normal INT */
> +       if (host->ops->uhs2_set_reg(host, DISABLE_INT)) {
> +               pr_err("%s: %s: UHS2 DISABLE_INT fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
> +               host->uhs2_dev_prop.node_id;
> +
> +       arg = ((UHS2_DEV_CMD_GO_DORMANT_STATE & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_4B |
> +               (UHS2_DEV_CMD_GO_DORMANT_STATE >> 8);
> +
> +       if (hibernate)
> +               payload[0] = UHS2_DEV_CMD_DORMANT_HIBER;
> +
> +       DBG("Begin GO_DORMANT_STATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
> +           header, arg, payload[0]);
> +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       /* Check Dormant State in Present */
> +       if (host->ops->uhs2_set_reg(host, CHECK_DORMANT)) {
> +               pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       host->ops->uhs2_disable_clk(host);
> +
> +       return 0;
> +}
> +
> +static int uhs2_change_speed(struct mmc_host *host)
> +{
> +       int err;
> +
> +       /* Change Speed Range */
> +       if (host->ops->uhs2_set_reg(host, SET_SPEED_B)) {
> +               pr_err("%s: %s: UHS2 SET_SPEED fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       err = uhs2_go_dormant(host, false);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       /* restore sd clock */
> +       mdelay(5);
> +       host->ops->uhs2_enable_clk(host);
> +
> +       /* Enable Normal INT */
> +       if (host->ops->uhs2_set_reg(host, ENABLE_INT)) {
> +               pr_err("%s: %s: UHS2 ENABLE_INT fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       if (host->ops->uhs2_detect_init(host)) {
> +               pr_err("%s: %s: uhs2_detect_init() fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * mmc_uhs2_rescan_try_freq - select UHS2 interface
> + * @host: MMC host
> + * @freq: Bus speed
> + *
> + * Try to select UHS2 interface and initialize the bus for a given
> + * frequency, @freq.
> + *
> + * Return:     0 on success, non-zero error on failure
> + */
> +int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq)
> +{
> +       int err = -EIO;
> +
> +       host->flags |= MMC_UHS2_SUPPORT;
> +       host->f_init = freq;
> +
> +       pr_debug("%s: %s: trying to init card at %u Hz\n",
> +                mmc_hostname(host), __func__, host->f_init);
> +
> +       mmc_power_up(host, 0);
> +       if (host->ops->uhs2_detect_init(host)) {
> +               pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
> +               err = UHS2_PHY_INIT_ERR;
> +               goto init_fail;
> +       }
> +
> +       if (uhs2_dev_init(host)) {
> +               pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
> +               goto init_fail;
> +       }
> +
> +       if (uhs2_enum(host)) {
> +               pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
> +               goto init_fail;
> +       }
> +
> +       if (uhs2_config_read(host)) {
> +               pr_err("%s: UHS2 INQUIRY_CONFIG fail!\n", mmc_hostname(host));
> +               goto init_fail;
> +       }
> +
> +       if (uhs2_config_write(host)) {
> +               pr_err("%s: UHS2 SET_COMMON_CONFIG fail!\n",
> +                      mmc_hostname(host));
> +               goto init_fail;
> +       }
> +
> +       mmc_delay(10);
> +
> +       /* Change to Speed Range B if it is supported */
> +       if (host->flags & MMC_UHS2_SPEED_B)
> +               if (uhs2_change_speed(host)) {
> +                       pr_err("%s: UHS2 uhs2_change_speed() fail!\n",
> +                              mmc_hostname(host));
> +                       goto init_fail;
> +               }
> +
> +       host->flags |= MMC_UHS2_INITIALIZED;
> +
> +       mmc_send_if_cond(host, host->ocr_avail);
> +
> +       /* On market, only can some SD cards support UHS-II so only call SD
> +        * attach process here.
> +        */

Not sure I understand this comment, can you please elaborate?

> +       if (!(host->caps2 & MMC_CAP2_NO_SD)) {
> +               err = mmc_attach_sd(host);

While looking at this, perhaps we should simply add a new mmc_bus_ops
for UHS-II cards, rather than re-using the mmc_sd_ops. Have you
considered that?

There are a couple of reasons why I think it could make sense.

*) The UHS-II code becomes more standalone, which seems like a good
idea since there really is lots of difference compared with the legacy
SD interface.
**) It would enable more flexibility and thus allow for easier UHS-II
optimizations. For example, it would make power management potentially
easier to support, as UHS-II re-initialization doesn't seem to have
much in common with legacy SD.

For those parts that are still common, sharing legacy SD functions via
common header files can be done, along the lines of what we do between
MMC and SD already.

> +               if (!err)
> +                       return 0;
> +       } else {
> +               err = -EIO;
> +       }
> +
> +init_fail:
> +       mmc_power_off(host);
> +       if (host->flags & MMC_UHS2_INITIALIZED)
> +               host->flags &= ~MMC_UHS2_INITIALIZED;
> +       host->flags &= ~MMC_UHS2_SUPPORT;
> +
> +       return err;
> +}
> +EXPORT_SYMBOL_GPL(mmc_uhs2_rescan_try_freq);
> diff --git a/drivers/mmc/core/uhs2.h b/drivers/mmc/core/uhs2.h
> new file mode 100644
> index 000000000000..e3389d4dda3b
> --- /dev/null
> +++ b/drivers/mmc/core/uhs2.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + *  driver/mmc/core/uhs2.h - UHS-II driver
> + *
> + * Header file for UHS-II packets, Host Controller registers and I/O
> + * accessors.
> + *
> + *  Copyright (C) 2014 Intel Corp, All Rights Reserved.
> + */
> +#ifndef MMC_UHS2_H
> +#define MMC_UHS2_H
> +
> +#include <linux/mmc/core.h>
> +#include <linux/mmc/host.h>
> +
> +#define UHS2_PHY_INIT_ERR      1
> +
> +int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq);
> +
> +#endif /* MMC_UHS2_H */
> --
> 2.27.0
>

Kind regards
Uffe

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface
  2020-08-18 11:41 ` Ulf Hansson
@ 2020-08-21 11:33   ` Ben Chuang
  2020-08-21 12:25     ` Ulf Hansson
  0 siblings, 1 reply; 5+ messages in thread
From: Ben Chuang @ 2020-08-21 11:33 UTC (permalink / raw)
  To: Ulf Hansson
  Cc: Adrian Hunter, linux-mmc, Linux Kernel Mailing List, Ben Chuang,
	Takahiro Akashi, greg.tu

On Tue, Aug 18, 2020 at 7:42 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>
> On Fri, 10 Jul 2020 at 13:08, Ben Chuang <benchuanggli@gmail.com> wrote:
> >
> > From: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> >
> > The flow of "interface selection and initialization" was a bit modified
> > for UHS-II card. This commit follows the sequence defined in SD
> > specification (Part 1).
> > See section 7.2.3 in "UHS-II Simplified Addendum."
> >
> > Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > ---
> >  drivers/mmc/core/Makefile |   2 +-
> >  drivers/mmc/core/bus.c    |   5 +-
> >  drivers/mmc/core/core.c   |  33 +-
> >  drivers/mmc/core/sd.c     |  26 ++
> >  drivers/mmc/core/uhs2.c   | 800 ++++++++++++++++++++++++++++++++++++++
> >  drivers/mmc/core/uhs2.h   |  20 +
> >  6 files changed, 882 insertions(+), 4 deletions(-)
> >  create mode 100644 drivers/mmc/core/uhs2.c
> >  create mode 100644 drivers/mmc/core/uhs2.h
> >
> > diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
> > index 95ffe008ebdf..e2a90dc98afc 100644
> > --- a/drivers/mmc/core/Makefile
> > +++ b/drivers/mmc/core/Makefile
> > @@ -8,7 +8,7 @@ mmc_core-y                      := core.o bus.o host.o \
> >                                    mmc.o mmc_ops.o sd.o sd_ops.o \
> >                                    sdio.o sdio_ops.o sdio_bus.o \
> >                                    sdio_cis.o sdio_io.o sdio_irq.o \
> > -                                  slot-gpio.o regulator.o
> > +                                  slot-gpio.o regulator.o uhs2.o
> >  mmc_core-$(CONFIG_OF)          += pwrseq.o
> >  obj-$(CONFIG_PWRSEQ_SIMPLE)    += pwrseq_simple.o
> >  obj-$(CONFIG_PWRSEQ_SD8787)    += pwrseq_sd8787.o
> > diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
> > index 70207f11a654..66d3e942f3fc 100644
> > --- a/drivers/mmc/core/bus.c
> > +++ b/drivers/mmc/core/bus.c
> > @@ -350,8 +350,9 @@ int mmc_add_card(struct mmc_card *card)
> >         } else {
> >                 pr_info("%s: new %s%s%s%s%s%s card at address %04x\n",
> >                         mmc_hostname(card->host),
> > -                       mmc_card_uhs(card) ? "ultra high speed " :
> > -                       (mmc_card_hs(card) ? "high speed " : ""),
> > +                       mmc_card_uhs2(card) ? "ultra high speed 2 " :
> > +                       (mmc_card_uhs(card) ? "ultra high speed 1 " :
>
> Perhaps use "UHS-I" and "UHS-II" instead.

OK, The next version will be changed.

>
> > +                       (mmc_card_hs(card) ? "high speed " : "")),
> >                         mmc_card_hs400(card) ? "HS400 " :
> >                         (mmc_card_hs200(card) ? "HS200 " : ""),
> >                         mmc_card_hs400es(card) ? "Enhanced strobe " : "",
> > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> > index c6540d56646b..e2534f3446ce 100644
> > --- a/drivers/mmc/core/core.c
> > +++ b/drivers/mmc/core/core.c
> > @@ -31,6 +31,7 @@
> >  #include <linux/mmc/mmc.h>
> >  #include <linux/mmc/sd.h>
> >  #include <linux/mmc/slot-gpio.h>
> > +#include <linux/mmc/uhs2.h>
> >
> >  #define CREATE_TRACE_POINTS
> >  #include <trace/events/mmc.h>
> > @@ -41,6 +42,7 @@
> >  #include "host.h"
> >  #include "sdio_bus.h"
> >  #include "pwrseq.h"
> > +#include "uhs2.h"
> >
> >  #include "mmc_ops.h"
> >  #include "sd_ops.h"
> > @@ -51,6 +53,7 @@
> >  #define SD_DISCARD_TIMEOUT_MS  (250)
> >
> >  static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
> > +static const unsigned int uhs2_freqs[] = { 52000000, 26000000 };
> >
> >  /*
> >   * Enabling software CRCs on the data blocks can be a significant (30%)
> > @@ -2165,9 +2168,10 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
> >                 if (!mmc_attach_sdio(host))
> >                         return 0;
> >
> > -       if (!(host->caps2 & MMC_CAP2_NO_SD))
> > +       if (!(host->caps2 & MMC_CAP2_NO_SD)) {
> >                 if (!mmc_attach_sd(host))
> >                         return 0;
> > +       }
> >
> >         if (!(host->caps2 & MMC_CAP2_NO_MMC))
> >                 if (!mmc_attach_mmc(host))
> > @@ -2300,6 +2304,33 @@ void mmc_rescan(struct work_struct *work)
> >                 goto out;
> >         }
> >
> > +       if (host->caps & MMC_CAP_UHS2) {
> > +               /*
> > +                * Start to try UHS-II initialization from 52MHz to 26MHz
> > +                * (RCLK range) per spec.
> > +                */
> > +               for (i = 0; i < ARRAY_SIZE(uhs2_freqs); i++) {
> > +                       unsigned int freq = uhs2_freqs[i];
> > +                       int err;
> > +
> > +                       err = mmc_uhs2_rescan_try_freq(host,
> > +                                                      max(freq, host->f_min));
> > +                       if (!err) {
> > +                               mmc_release_host(host);
> > +                               goto out;
> > +                       }
> > +
> > +                       if (err == UHS2_PHY_INIT_ERR)
> > +                               /* UHS2 IF detect or Lane Sync error.
> > +                                * Try legacy interface.
> > +                                */
> > +                               break;
> > +
> > +                       if (freq <= host->f_min)
> > +                               break;
> > +               }
>
> Assuming we change the initialization order, trying to initialize the
> legacy SD interface first to figure out if UHS-II is supported, then I
> think we should be able to move the entire code above into a the
> UHS-II specific code/path.

If the host tries to use the SD interface first,
some failure status needs to be considered.

For example, first run in SD mode, try UHS-II interface failure,
 and then return to SD flow again.
I don't know a good way to go back to SD flow again.

>
> > +       }
> > +
> >         for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> >                 unsigned int freq = freqs[i];
> >                 if (freq > host->f_max) {
> > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> > index 5a2210c25aa7..c5b071bd98b3 100644
> > --- a/drivers/mmc/core/sd.c
> > +++ b/drivers/mmc/core/sd.c
> > @@ -901,6 +901,20 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
> >                 err = mmc_read_switch(card);
> >                 if (err)
> >                         return err;
> > +               if (host->flags & MMC_UHS2_INITIALIZED) {
>
> Rather than using host->flags, to tweak the behavior of
> mmc_sd_setup_card() to support UHS-II, I would prefer to give
> mmc_sd_setup_card() a new in-parameter that it can look at instead.

Do you mean that adding a new in-parameter to mmc_sd_setup_card() likes this
mmc_sd_setup_card(struct mmc_host *, struct mmc_card *, boot reinit,
boot uhsii); ?

>
> > +                       u8 status[64];
> > +                       /*
> > +                        * send CMD6 to set Maximum Power Consumption
> > +                        * to get better performance
> > +                        */
> > +                       err = mmc_sd_switch(card, 0, 3,
> > +                                           SD_SET_CURRENT_LIMIT_1000, status);
> > +                       if (!err) {
> > +                               err = mmc_sd_switch(card, 1, 3,
> > +                                                   SD_SET_CURRENT_LIMIT_1000,
> > +                                                   status);
> > +                       }
> > +               }
> >         }
> >
> >         /*
> > @@ -1043,6 +1057,11 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
> >         if (err)
> >                 goto free_card;
> >
> > +       /* For UHS2, skip the UHS-I initialization. */
> > +       if ((host->flags & MMC_UHS2_SUPPORT) &&
> > +           (host->flags & MMC_UHS2_INITIALIZED))
> > +               goto done;
>
> mmc_sd_init_card() is also called at system resume, to re-initialize the card.
>
> Re-initialization is going to be needed for UHS-II cards as well,
> since we should ideally avoid wasting energy in system suspend state
> for these cards as well.
>
> Perhaps you haven't looked at that part yet? Or I may be missing something here?

Yes, I didn't look at that power management. It should be considered.

>
> > +
> >         /*
> >          * If the card has not been power cycled, it may still be using 1.8V
> >          * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
> > @@ -1334,6 +1353,13 @@ int mmc_attach_sd(struct mmc_host *host)
> >
> >         rocr = mmc_select_voltage(host, ocr);
> >
> > +       /*
> > +        * Some cards have zero value of rocr in UHS-II mode. Assign host's ocr
> > +        * value to rocr.
> > +        */
> > +       if ((host->flags & MMC_UHS2_INITIALIZED) && !rocr)
> > +               rocr = host->ocr_avail;
>
> As stated already earlier above, we should probably be able to move
> any UHS-II specific bits to the UHS-II code/path.
>
> > +
> >         /*
> >          * Can we support the voltage(s) of the card(s)?
> >          */
> > diff --git a/drivers/mmc/core/uhs2.c b/drivers/mmc/core/uhs2.c
> > new file mode 100644
> > index 000000000000..a3b20ac6f315
> > --- /dev/null
> > +++ b/drivers/mmc/core/uhs2.c
> > @@ -0,0 +1,800 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/*
> > + *  linux/drivers/mmc/core/uhs2.c - UHS-II driver
> > + *
> > + *  Copyright (C) 2014 Intel Corp, All Rights Reserved.
> > + *  Copyright (C) 2020 Genesys Logic, Inc.
> > + *  Authors: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> > + *  Copyright (C) 2020 Linaro Limited
> > + *  Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > + */
> > +
> > +#include <asm/byteorder.h>
> > +#include <linux/err.h>
> > +#include <linux/slab.h>
> > +
> > +#include <linux/mmc/host.h>
> > +#include <linux/mmc/card.h>
> > +#include <linux/mmc/mmc.h>
> > +#include <linux/mmc/core.h>
> > +#include <linux/mmc/sdio.h>
> > +#include <linux/mmc/slot-gpio.h>
> > +#include <linux/mmc/uhs2.h>
> > +
> > +#include "uhs2.h"
> > +#include "mmc_ops.h"
> > +#include "sd_ops.h"
> > +#include "core.h"
> > +
> > +#define DBG(f, x...) \
> > +       pr_warn("[%s()]: " f, __func__, ## x)
> > +
> > +/**
> > + * uhs2_cmd_assemble - assemble and build up uhs2 command
> > + * @cmd:       MMC command
> > + * @uhs2_cmd:  UHS2 command
> > + * @header:    Value of packet header
> > + * @arg:       Argument of packet
> > + * @payload:   Payload of packet
> > + * @plen:      Payload length
> > + * @resp:      Buffer for response
> > + * @resp_len:  Response buffer length
> > + *
> > + * resp is inputted outside which should be a variable created by caller
> > + * so caller should handle it. For SD command, there is no uhs2_resp and
> > + * response should be stored in resp of mmc_command.
> > + */
> > +static void uhs2_cmd_assemble(struct mmc_command *cmd,
> > +                             struct uhs2_command *uhs2_cmd,
> > +                             u16 header, u16 arg,
> > +                             u32 *payload, u8 plen, u8 *resp, u8 resp_len)
> > +{
> > +       uhs2_cmd->header = header;
> > +       uhs2_cmd->arg = arg;
> > +       uhs2_cmd->payload = payload;
> > +       uhs2_cmd->payload_len = plen * sizeof(u32);
> > +       uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
> > +
> > +       cmd->uhs2_cmd = uhs2_cmd;
> > +       cmd->uhs2_resp = resp;
> > +       cmd->uhs2_resp_len = resp_len;
> > +
> > +       pr_debug("%s: uhs2_cmd: header=0x%x arg=0x%x\n",
> > +                __func__, uhs2_cmd->header, uhs2_cmd->arg);
> > +       pr_debug("%s:           payload_len=%d packet_len=%d resp_len=%d\n",
> > +                __func__, uhs2_cmd->payload_len, uhs2_cmd->packet_len,
> > +               cmd->uhs2_resp_len);
>
> I noticed that there is lots of debug code around. I understand that
> it's useful during development, but I think we should be able to
> remove some of it. Can you please have a look and clean up that?

OK, debug codes will be cleared.

>
> > +}
> > +
> > +static int uhs2_dev_init(struct mmc_host *host)
> > +{
> > +       struct mmc_command cmd = {0};
> > +       struct uhs2_command uhs2_cmd = {};
> > +       u32 cnt;
> > +       u32 dap, gap, gap1;
> > +       u16 header = 0, arg = 0;
> > +       u32 payload[1];
> > +       u8 plen = 1;
> > +       u8 gd = 0, cf = 1;
> > +       u8 resp[6] = {0};
> > +       u8 resp_len = 6;
> > +       int err;
> > +
> > +       dap = host->uhs2_caps.dap;
> > +       gap = host->uhs2_caps.gap;
> > +
> > +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> > +       arg = ((UHS2_DEV_CMD_DEVICE_INIT & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_4B |
> > +               (UHS2_DEV_CMD_DEVICE_INIT >> 8);
> > +
> > +       /* need this for some cards */
> > +       cmd.busy_timeout = 1000;
>
> Is this according to spec? Please add defines for timeout values.

In UHS-II Addenum, table 6-25: device timing parameters in CM_TRAN,
Please see `initialization' row in table 6-25.

I will define it like "#define UHSII_DEVINIT_CMD_TIMEOUT 1000".

>
> > +
> > +       for (cnt = 0; cnt < 30; cnt++) {
> > +               payload[0] = ((dap & 0xF) << 12) |
> > +                       (cf << 11) |
> > +                       ((gd & 0xF) << 4) |
> > +                       (gap & 0xF);
> > +
> > +               uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> > +                                 payload, plen, resp, resp_len);
> > +
> > +               DBG("Begin DEVICE_INIT, header=0x%x, arg=0x%x, payload=0x%x.\n",
> > +                   header, arg, payload[0]);
> > +
> > +               DBG("Sending DEVICE_INIT. Count = %d\n", cnt);
> > +               err = mmc_wait_for_cmd(host, &cmd, 0);
>
> Debug code, please clean this up...

OK.

>
> > +
> > +               if (err) {
> > +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                              mmc_hostname(host), __func__, err);
> > +                       return -EIO;
> > +               }
> > +
> > +               if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
>
> Debug code, please clean this up. I am stopping from commenting on
> that, as stated, please have a look at all the code to clean this up.

OK, I will remove debug codes as much as possible.

>
> > +                       int i;
> > +
> > +                       pr_warn("%s: DEVICE_INIT response is: ",
> > +                               mmc_hostname(host));
> > +                       for (i = 0; i < resp_len; i++)
> > +                               pr_warn("0x%x ", resp[i]);
> > +                       pr_warn("\n");
> > +               }
> > +
> > +               if (resp[3] != (UHS2_DEV_CMD_DEVICE_INIT & 0xFF)) {
> > +                       pr_err("%s: DEVICE_INIT response is wrong!\n",
> > +                              mmc_hostname(host));
> > +                       return -EIO;
> > +               }
> > +
> > +               if (resp[5] & 0x8) {
> > +                       DBG("CF is set, device is initialized!\n");
> > +                       host->group_desc = gd;
> > +                       break;
> > +               }
> > +               gap1 = resp[4] & 0x0F;
> > +               if (gap == gap1)
> > +                       gd++;
> > +       }
> > +       if (cnt == 30) {
> > +               pr_err("%s: DEVICE_INIT fail, already 30 times!\n",
> > +                      mmc_hostname(host));
> > +               return -EIO;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +static int uhs2_enum(struct mmc_host *host)
> > +{
> > +       struct mmc_command cmd = {0};
> > +       struct uhs2_command uhs2_cmd = {};
> > +       u16 header = 0, arg = 0;
> > +       u32 payload[1];
> > +       u8 plen = 1;
> > +       u8 id_f = 0xF, id_l = 0x0;
> > +       u8 resp[8] = {0};
> > +       u8 resp_len = 8;
> > +       int err;
> > +
> > +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> > +       arg = ((UHS2_DEV_CMD_ENUMERATE & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_4B |
> > +               (UHS2_DEV_CMD_ENUMERATE >> 8);
> > +
> > +       payload[0] = (id_f << 4) | id_l;
> > +
> > +       DBG("Begin ENUMERATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
> > +           header, arg, payload[0]);
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> > +                         resp, resp_len);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > +               int i;
> > +
> > +               pr_warn("%s: ENUMERATE response is: ", mmc_hostname(host));
> > +               for (i = 0; i < resp_len; i++)
> > +                       pr_warn("0x%x ", resp[i]);
> > +               pr_warn("\n");
> > +       }
> > +
> > +       if (resp[3] != (UHS2_DEV_CMD_ENUMERATE & 0xFF)) {
> > +               pr_err("%s: ENUMERATE response is wrong!\n",
> > +                      mmc_hostname(host));
> > +               return -EIO;
> > +       }
> > +
> > +       id_f = (resp[4] >> 4) & 0xF;
> > +       id_l = resp[4] & 0xF;
> > +       DBG("id_f = %d, id_l = %d.\n", id_f, id_l);
> > +       DBG("Enumerate Cmd Completed. No. of Devices connected = %d\n",
> > +           id_l - id_f + 1);
> > +       host->uhs2_dev_prop.node_id = id_f;
> > +
> > +       return 0;
> > +}
> > +
> > +static int uhs2_config_read(struct mmc_host *host)
> > +{
> > +       struct mmc_command cmd = {0};
> > +       struct uhs2_command uhs2_cmd = {};
> > +       u16 header = 0, arg = 0;
> > +       u32 cap;
> > +       int err;
> > +
> > +       DBG("INQUIRY_CFG: read Generic Caps.\n");
> > +       header = UHS2_NATIVE_PACKET |
> > +                UHS2_PACKET_TYPE_CCMD |
> > +                host->uhs2_dev_prop.node_id;
> > +       arg = ((UHS2_DEV_CONFIG_GEN_CAPS & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_READ |
> > +               UHS2_NATIVE_CMD_PLEN_4B |
> > +               (UHS2_DEV_CONFIG_GEN_CAPS >> 8);
> > +
> > +       DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> > +           header, arg);
> > +       /* There is no payload because per spec, there should be
> > +        * no payload field for read CCMD.
> > +        * Plen is set in arg. Per spec, plen for read CCMD
> > +        * represents the len of read data which is assigned in payload
> > +        * of following RES (p136).
> > +        */
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > +               int i;
> > +
> > +               pr_warn("%s: INQUIRY_CFG generic response is: ",
> > +                       mmc_hostname(host));
> > +               for (i = 0; i < 2; i++)
> > +                       pr_warn("0x%x ", cmd.resp[i]);
> > +               pr_warn("\n");
> > +       }
> > +
> > +       cap = cmd.resp[0];
> > +       DBG("Device Generic Caps (0-31) is: 0x%x.\n", cap);
> > +       host->uhs2_dev_prop.n_lanes = (cap >> UHS2_DEV_CONFIG_N_LANES_POS) &
> > +                                       UHS2_DEV_CONFIG_N_LANES_MASK;
> > +       host->uhs2_dev_prop.dadr_len = (cap >> UHS2_DEV_CONFIG_DADR_POS) &
> > +                                       UHS2_DEV_CONFIG_DADR_MASK;
> > +       host->uhs2_dev_prop.app_type = (cap >> UHS2_DEV_CONFIG_APP_POS) &
> > +                                       UHS2_DEV_CONFIG_APP_MASK;
> > +
> > +       DBG("INQUIRY_CFG: read PHY Caps.\n");
> > +       arg = ((UHS2_DEV_CONFIG_PHY_CAPS & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_READ |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_PHY_CAPS >> 8);
> > +
> > +       DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> > +           header, arg);
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > +               int i;
> > +
> > +               pr_warn("%s: INQUIRY_CFG PHY response is: ",
> > +                       mmc_hostname(host));
> > +               for (i = 0; i < 2; i++)
> > +                       pr_warn("0x%x ", cmd.resp[i]);
> > +               pr_warn("\n");
> > +       }
> > +
> > +       cap = cmd.resp[0];
> > +       DBG("Device PHY Caps (0-31) is: 0x%x.\n", cap);
> > +       host->uhs2_dev_prop.phy_minor_rev = cap &
> > +                                       UHS2_DEV_CONFIG_PHY_MINOR_MASK;
> > +       host->uhs2_dev_prop.phy_major_rev = (cap >>
> > +                                       UHS2_DEV_CONFIG_PHY_MAJOR_POS) &
> > +                                       UHS2_DEV_CONFIG_PHY_MAJOR_MASK;
> > +       host->uhs2_dev_prop.can_hibernate = (cap >>
> > +                                       UHS2_DEV_CONFIG_CAN_HIBER_POS) &
> > +                                       UHS2_DEV_CONFIG_CAN_HIBER_MASK;
> > +
> > +       cap = cmd.resp[1];
> > +       DBG("Device PHY Caps (32-63) is: 0x%x.\n", cap);
> > +       host->uhs2_dev_prop.n_lss_sync = cap & UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> > +       host->uhs2_dev_prop.n_lss_dir = (cap >>
> > +                                       UHS2_DEV_CONFIG_N_LSS_DIR_POS) &
> > +                                       UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > +       if (host->uhs2_dev_prop.n_lss_sync == 0)
> > +               host->uhs2_dev_prop.n_lss_sync = 16 << 2;
> > +       else
> > +               host->uhs2_dev_prop.n_lss_sync <<= 2;
> > +
> > +       if (host->uhs2_dev_prop.n_lss_dir == 0)
> > +               host->uhs2_dev_prop.n_lss_dir = 16 << 3;
> > +       else
> > +               host->uhs2_dev_prop.n_lss_dir <<= 3;
> > +
> > +       DBG("INQUIRY_CFG: read LINK-TRAN Caps.\n");
> > +       arg = ((UHS2_DEV_CONFIG_LINK_TRAN_CAPS & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_READ |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_LINK_TRAN_CAPS >> 8);
> > +
> > +       DBG("Begin INQUIRY_CFG, header=0x%x, arg=0x%x.\n",
> > +           header, arg);
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       if (IS_ENABLED(CONFIG_MMC_DEBUG)) {
> > +               int i;
> > +
> > +               pr_warn("%s: INQUIRY_CFG Link-Tran response is: ",
> > +                       mmc_hostname(host));
> > +               for (i = 0; i < 2; i++)
> > +                       pr_warn("0x%x ", cmd.resp[i]);
> > +               pr_warn("\n");
> > +       }
> > +
> > +       cap = cmd.resp[0];
> > +       DBG("Device LINK-TRAN Caps (0-31) is: 0x%x.\n", cap);
> > +       host->uhs2_dev_prop.link_minor_rev = cap &
> > +                                       UHS2_DEV_CONFIG_LT_MINOR_MASK;
> > +       host->uhs2_dev_prop.link_major_rev = (cap >>
> > +                                       UHS2_DEV_CONFIG_LT_MAJOR_POS) &
> > +                                       UHS2_DEV_CONFIG_LT_MAJOR_MASK;
> > +       host->uhs2_dev_prop.n_fcu = (cap >> UHS2_DEV_CONFIG_N_FCU_POS) &
> > +                                       UHS2_DEV_CONFIG_N_FCU_MASK;
> > +       host->uhs2_dev_prop.dev_type = (cap >> UHS2_DEV_CONFIG_DEV_TYPE_POS) &
> > +                                       UHS2_DEV_CONFIG_DEV_TYPE_MASK;
> > +       host->uhs2_dev_prop.maxblk_len = (cap >>
> > +                                       UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) &
> > +                                       UHS2_DEV_CONFIG_MAX_BLK_LEN_MASK;
> > +
> > +       cap = cmd.resp[1];
> > +       DBG("Device LINK-TRAN Caps (32-63) is: 0x%x.\n", cap);
> > +       host->uhs2_dev_prop.n_data_gap = cap & UHS2_DEV_CONFIG_N_DATA_GAP_MASK;
> > +       if (host->uhs2_dev_prop.n_fcu == 0)
> > +               host->uhs2_dev_prop.n_fcu = 256;
> > +
> > +       return 0;
> > +}
> > +
> > +static int uhs2_config_write(struct mmc_host *host)
> > +{
> > +       struct mmc_command cmd = {0};
> > +       struct uhs2_command uhs2_cmd = {};
> > +       u16 header = 0, arg = 0;
> > +       u32 nTry;
> > +       u32 payload[2];
> > +       u8 nMinDataGap;
> > +       u8 plen;
> > +       int err;
> > +       u8 resp[5] = {0};
> > +       u8 resp_len = 5;
> > +       /*
> > +        * must long enough for RECV_SW_DIR == 2;
> > +        * need lss_dir at least 4 for GL9755 device
> > +        * max compitable g_lss_dir = 0
> > +        */
> > +       u32 g_lss_dir = 0;
> > +
> > +       DBG("SET_COMMON_CFG: write Generic Settings.\n");
> > +       header = UHS2_NATIVE_PACKET |
> > +                UHS2_PACKET_TYPE_CCMD | host->uhs2_dev_prop.node_id;
> > +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_GEN_SET >> 8);
> > +
> > +       if (host->uhs2_dev_prop.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
> > +           host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
> > +               /* Support HD */
> > +               DBG("Both Host and device support 2L-HD.\n");
> > +               host->flags |= MMC_UHS2_2L_HD;
> > +               host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > +               host->uhs2_dev_prop.n_lanes_set =
> > +                               UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > +               nMinDataGap = 1;
> > +       } else {
> > +               /* Only support 2L-FD so far */
> > +               host->flags &= ~MMC_UHS2_2L_HD;
> > +               host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > +               host->uhs2_dev_prop.n_lanes_set =
> > +                               UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > +               nMinDataGap = 3;
> > +       }
> > +
> > +       plen = 2;
> > +       payload[0] = host->uhs2_dev_prop.n_lanes_set <<
> > +                    UHS2_DEV_CONFIG_N_LANES_POS;
> > +       payload[1] = 0;
> > +       payload[0] = cpu_to_be32(payload[0]);
> > +       payload[1] = cpu_to_be32(payload[1]);
> > +
> > +       DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x\n", header, arg);
> > +       DBG("UHS2 write Generic Settings %08x %08x\n",
> > +           payload[0], payload[1]);
> > +       DBG("flags=%08x dev_prop.n_lanes_set=%x host_caps.n_lanes_set=%x\n",
> > +           host->flags,
> > +           host->uhs2_dev_prop.n_lanes_set,
> > +           host->uhs2_caps.n_lanes_set);
> > +
> > +       /*
> > +        * There is no payload because per spec, there should be
> > +        * no payload field for read CCMD.
> > +        * Plen is set in arg. Per spec, plen for read CCMD
> > +        * represents the len of read data which is assigned in payload
> > +        * of following RES (p136).
> > +        */
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       DBG("SET_COMMON_CFG: PHY Settings.\n");
> > +       arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_PHY_SET >> 8);
> > +
> > +       for (nTry = 0; nTry < 2; nTry++) {
> > +               plen = 2;
> > +
> > +               if (host->uhs2_caps.speed_range ==
> > +                       UHS2_DEV_CONFIG_PHY_SET_SPEED_B) {
> > +                       host->flags |= MMC_UHS2_SPEED_B;
> > +                       host->uhs2_dev_prop.speed_range_set =
> > +                               UHS2_DEV_CONFIG_PHY_SET_SPEED_B;
> > +                       DBG("set dev_prop.speed_range_set to SPEED_B\n");
> > +               } else {
> > +                       host->uhs2_dev_prop.speed_range_set =
> > +                               UHS2_DEV_CONFIG_PHY_SET_SPEED_A;
> > +                       host->flags &= ~MMC_UHS2_SPEED_B;
> > +                       DBG("set dev_prop.speed_range_set to SPEED_A\n");
> > +               }
> > +
> > +               payload[0] = host->uhs2_dev_prop.speed_range_set <<
> > +                               UHS2_DEV_CONFIG_PHY_SET_SPEED_POS;
> > +
> > +               host->uhs2_dev_prop.n_lss_sync_set =
> > +                       (min(host->uhs2_dev_prop.n_lss_sync,
> > +                       host->uhs2_caps.n_lss_sync) >> 2) &
> > +                       UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> > +               host->uhs2_caps.n_lss_sync_set =
> > +                       host->uhs2_dev_prop.n_lss_sync_set;
> > +
> > +               if (nTry) {
> > +                       host->uhs2_dev_prop.n_lss_dir_set =
> > +                               (max(host->uhs2_dev_prop.n_lss_dir,
> > +                               host->uhs2_caps.n_lss_dir) >> 3) &
> > +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > +                       host->uhs2_caps.n_lss_dir_set =
> > +                               host->uhs2_dev_prop.n_lss_dir_set;
> > +                       payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
> > +                               UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> > +                               host->uhs2_dev_prop.n_lss_sync_set;
> > +               } else {
> > +                       host->uhs2_caps.n_lss_dir_set =
> > +                               (host->uhs2_dev_prop.n_lss_dir >> 3) &
> > +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > +                       host->uhs2_dev_prop.n_lss_dir_set =
> > +                               ((host->uhs2_caps.n_lss_dir >> 3) + 1) &
> > +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> > +               }
> > +
> > +               if (!g_lss_dir) {
> > +                       host->uhs2_dev_prop.n_lss_dir_set = 0;
> > +               } else {
> > +                       host->uhs2_dev_prop.n_lss_dir_set =
> > +                               max((u8)g_lss_dir,
> > +                                   host->uhs2_dev_prop.n_lss_dir_set);
> > +               }
> > +
> > +               payload[1] = (host->uhs2_dev_prop.n_lss_dir_set <<
> > +                               UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> > +                               host->uhs2_dev_prop.n_lss_sync_set;
> > +               payload[0] = cpu_to_be32(payload[0]);
> > +               payload[1] = cpu_to_be32(payload[1]);
> > +
> > +               DBG("UHS2 SET PHY Settings  %08x %08x\n",
> > +                   payload[0], payload[1]);
> > +               DBG("host->flags=%08x dev_prop.speed_range_set=%x\n",
> > +                   host->flags,
> > +                   host->uhs2_dev_prop.speed_range_set);
> > +               DBG("dev_prop.n_lss_sync_set=%x host_caps.n_lss_sync_set=%x\n",
> > +                   host->uhs2_dev_prop.n_lss_sync_set,
> > +                   host->uhs2_caps.n_lss_sync_set);
> > +               DBG("dev_prop.n_lss_dir_set=%x host_caps.n_lss_dir_set=%x\n",
> > +                   host->uhs2_dev_prop.n_lss_dir_set,
> > +                   host->uhs2_caps.n_lss_dir_set);
> > +
> > +               DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n",
> > +                   header, arg);
> > +               DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n",
> > +                   payload[0], payload[1]);
> > +
> > +               resp_len = 4;
> > +               memset(resp, 0, sizeof(resp));
> > +
> > +               uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> > +                                 payload, plen, resp, resp_len);
> > +
> > +               err = mmc_wait_for_cmd(host, &cmd, 0);
> > +               if (err) {
> > +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                              mmc_hostname(host), __func__, err);
> > +                       return -EIO;
> > +               }
> > +
> > +               if (!(resp[2] & 0x80))
> > +                       break;
> > +
> > +               DBG("%s: %s: UHS2 SET PHY Settings fail, res= 0x%x!\n",
> > +                   mmc_hostname(host), __func__,  resp[2]);
> > +       }
> > +
> > +       DBG("SET_COMMON_CFG: LINK-TRAN Settings.\n");
> > +       arg = ((UHS2_DEV_CONFIG_LINK_TRAN_SET & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_LINK_TRAN_SET >> 8);
> > +
> > +       plen = 2;
> > +
> > +       if (host->uhs2_dev_prop.app_type == UHS2_DEV_CONFIG_APP_SD_MEM)
> > +               host->uhs2_dev_prop.maxblk_len_set =
> > +                       UHS2_DEV_CONFIG_LT_SET_MAX_BLK_LEN;
> > +       else
> > +               host->uhs2_dev_prop.maxblk_len_set =
> > +                       min(host->uhs2_dev_prop.maxblk_len,
> > +                           host->uhs2_caps.maxblk_len);
> > +       host->uhs2_caps.maxblk_len_set = host->uhs2_dev_prop.maxblk_len_set;
> > +
> > +       host->uhs2_dev_prop.n_fcu_set =
> > +               min(host->uhs2_dev_prop.n_fcu,
> > +                   host->uhs2_caps.n_fcu);
> > +       host->uhs2_caps.n_fcu_set = host->uhs2_dev_prop.n_fcu_set;
> > +
> > +       host->uhs2_dev_prop.n_data_gap_set =
> > +               max(nMinDataGap, host->uhs2_dev_prop.n_data_gap);
> > +
> > +       host->uhs2_caps.n_data_gap_set = host->uhs2_dev_prop.n_data_gap_set;
> > +
> > +       host->uhs2_caps.max_retry_set = 3;
> > +       host->uhs2_dev_prop.max_retry_set = host->uhs2_caps.max_retry_set;
> > +
> > +       payload[0] = (host->uhs2_dev_prop.maxblk_len_set <<
> > +                       UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) |
> > +                       (host->uhs2_dev_prop.max_retry_set <<
> > +                       UHS2_DEV_CONFIG_LT_SET_MAX_RETRY_POS) |
> > +                       (host->uhs2_dev_prop.n_fcu_set <<
> > +                       UHS2_DEV_CONFIG_N_FCU_POS);
> > +       payload[1] = host->uhs2_dev_prop.n_data_gap_set;
> > +       payload[0] = cpu_to_be32(payload[0]);
> > +       payload[1] = cpu_to_be32(payload[1]);
> > +
> > +       DBG("Begin SET_COMMON_CFG header=0x%x arg=0x%x\n", header, arg);
> > +       DBG("\t\tpayload[0]=0x%x payload[1]=0x%x\n", payload[0], payload[1]);
> > +
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       DBG("SET_COMMON_CFG: Set Config Completion.\n");
> > +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_GEN_SET >> 8);
> > +
> > +       plen = 2;
> > +       payload[0] = 0;
> > +       payload[1] = UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE;
> > +       payload[0] = cpu_to_be32(payload[0]);
> > +       payload[1] = cpu_to_be32(payload[1]);
> > +
> > +       DBG("Begin SET_COMMON_CFG, header=0x%x, arg=0x%x, payload[0] = 0x%x.\n",
> > +           header, arg, payload[0]);
> > +       resp_len = 5;
> > +       memset(resp, 0, sizeof(resp));
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> > +                         resp, resp_len);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       /* Set host Config Setting registers */
> > +       if (host->ops->uhs2_set_reg(host, SET_CONFIG)) {
> > +               pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +static int uhs2_go_dormant(struct mmc_host *host, bool hibernate)
> > +{
> > +       struct mmc_command cmd = {0};
> > +       struct uhs2_command uhs2_cmd = {};
> > +       u16 header = 0, arg = 0;
> > +       u32 payload[1];
> > +       u8 plen = 1;
> > +       int err;
> > +
> > +       /* Disable Normal INT */
> > +       if (host->ops->uhs2_set_reg(host, DISABLE_INT)) {
> > +               pr_err("%s: %s: UHS2 DISABLE_INT fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
> > +               host->uhs2_dev_prop.node_id;
> > +
> > +       arg = ((UHS2_DEV_CMD_GO_DORMANT_STATE & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_WRITE |
> > +               UHS2_NATIVE_CMD_PLEN_4B |
> > +               (UHS2_DEV_CMD_GO_DORMANT_STATE >> 8);
> > +
> > +       if (hibernate)
> > +               payload[0] = UHS2_DEV_CMD_DORMANT_HIBER;
> > +
> > +       DBG("Begin GO_DORMANT_STATE, header=0x%x, arg=0x%x, payload=0x%x.\n",
> > +           header, arg, payload[0]);
> > +       uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen, NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       /* Check Dormant State in Present */
> > +       if (host->ops->uhs2_set_reg(host, CHECK_DORMANT)) {
> > +               pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +       host->ops->uhs2_disable_clk(host);
> > +
> > +       return 0;
> > +}
> > +
> > +static int uhs2_change_speed(struct mmc_host *host)
> > +{
> > +       int err;
> > +
> > +       /* Change Speed Range */
> > +       if (host->ops->uhs2_set_reg(host, SET_SPEED_B)) {
> > +               pr_err("%s: %s: UHS2 SET_SPEED fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +       err = uhs2_go_dormant(host, false);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       /* restore sd clock */
> > +       mdelay(5);
> > +       host->ops->uhs2_enable_clk(host);
> > +
> > +       /* Enable Normal INT */
> > +       if (host->ops->uhs2_set_reg(host, ENABLE_INT)) {
> > +               pr_err("%s: %s: UHS2 ENABLE_INT fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +       if (host->ops->uhs2_detect_init(host)) {
> > +               pr_err("%s: %s: uhs2_detect_init() fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> > + * mmc_uhs2_rescan_try_freq - select UHS2 interface
> > + * @host: MMC host
> > + * @freq: Bus speed
> > + *
> > + * Try to select UHS2 interface and initialize the bus for a given
> > + * frequency, @freq.
> > + *
> > + * Return:     0 on success, non-zero error on failure
> > + */
> > +int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq)
> > +{
> > +       int err = -EIO;
> > +
> > +       host->flags |= MMC_UHS2_SUPPORT;
> > +       host->f_init = freq;
> > +
> > +       pr_debug("%s: %s: trying to init card at %u Hz\n",
> > +                mmc_hostname(host), __func__, host->f_init);
> > +
> > +       mmc_power_up(host, 0);
> > +       if (host->ops->uhs2_detect_init(host)) {
> > +               pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
> > +               err = UHS2_PHY_INIT_ERR;
> > +               goto init_fail;
> > +       }
> > +
> > +       if (uhs2_dev_init(host)) {
> > +               pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
> > +               goto init_fail;
> > +       }
> > +
> > +       if (uhs2_enum(host)) {
> > +               pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
> > +               goto init_fail;
> > +       }
> > +
> > +       if (uhs2_config_read(host)) {
> > +               pr_err("%s: UHS2 INQUIRY_CONFIG fail!\n", mmc_hostname(host));
> > +               goto init_fail;
> > +       }
> > +
> > +       if (uhs2_config_write(host)) {
> > +               pr_err("%s: UHS2 SET_COMMON_CONFIG fail!\n",
> > +                      mmc_hostname(host));
> > +               goto init_fail;
> > +       }
> > +
> > +       mmc_delay(10);
> > +
> > +       /* Change to Speed Range B if it is supported */
> > +       if (host->flags & MMC_UHS2_SPEED_B)
> > +               if (uhs2_change_speed(host)) {
> > +                       pr_err("%s: UHS2 uhs2_change_speed() fail!\n",
> > +                              mmc_hostname(host));
> > +                       goto init_fail;
> > +               }
> > +
> > +       host->flags |= MMC_UHS2_INITIALIZED;
> > +
> > +       mmc_send_if_cond(host, host->ocr_avail);
> > +
> > +       /* On market, only can some SD cards support UHS-II so only call SD
> > +        * attach process here.
> > +        */
>
> Not sure I understand this comment, can you please elaborate?

Please ignore the comment. I will delete it.

>
> > +       if (!(host->caps2 & MMC_CAP2_NO_SD)) {
> > +               err = mmc_attach_sd(host);
>
> While looking at this, perhaps we should simply add a new mmc_bus_ops
> for UHS-II cards, rather than re-using the mmc_sd_ops. Have you
> considered that?

Thanks for this suggestion. I'll mull it over.

>
> There are a couple of reasons why I think it could make sense.
>
> *) The UHS-II code becomes more standalone, which seems like a good
> idea since there really is lots of difference compared with the legacy
> SD interface.
> **) It would enable more flexibility and thus allow for easier UHS-II
> optimizations. For example, it would make power management potentially
> easier to support, as UHS-II re-initialization doesn't seem to have
> much in common with legacy SD.
>

I haven't studied the power management subsystem part at present.
If creating a new mmc_bus_ops can help simplify the power
management,it can be considered.
So there's currently no plan to modify the architecture.

> For those parts that are still common, sharing legacy SD functions via
> common header files can be done, along the lines of what we do between
> MMC and SD already.

Thanks for your comments . I still have a lot to learn and study.

>
> > +               if (!err)
> > +                       return 0;
> > +       } else {
> > +               err = -EIO;
> > +       }
> > +
> > +init_fail:
> > +       mmc_power_off(host);
> > +       if (host->flags & MMC_UHS2_INITIALIZED)
> > +               host->flags &= ~MMC_UHS2_INITIALIZED;
> > +       host->flags &= ~MMC_UHS2_SUPPORT;
> > +
> > +       return err;
> > +}
> > +EXPORT_SYMBOL_GPL(mmc_uhs2_rescan_try_freq);
> > diff --git a/drivers/mmc/core/uhs2.h b/drivers/mmc/core/uhs2.h
> > new file mode 100644
> > index 000000000000..e3389d4dda3b
> > --- /dev/null
> > +++ b/drivers/mmc/core/uhs2.h
> > @@ -0,0 +1,20 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +/*
> > + *  driver/mmc/core/uhs2.h - UHS-II driver
> > + *
> > + * Header file for UHS-II packets, Host Controller registers and I/O
> > + * accessors.
> > + *
> > + *  Copyright (C) 2014 Intel Corp, All Rights Reserved.
> > + */
> > +#ifndef MMC_UHS2_H
> > +#define MMC_UHS2_H
> > +
> > +#include <linux/mmc/core.h>
> > +#include <linux/mmc/host.h>
> > +
> > +#define UHS2_PHY_INIT_ERR      1
> > +
> > +int mmc_uhs2_rescan_try_freq(struct mmc_host *host, unsigned int freq);
> > +
> > +#endif /* MMC_UHS2_H */
> > --
> > 2.27.0
> >
>
> Kind regards
> Uffe

Best regards,
Ben

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface
  2020-08-21 11:33   ` Ben Chuang
@ 2020-08-21 12:25     ` Ulf Hansson
  2020-08-21 14:28       ` Adrian Hunter
  0 siblings, 1 reply; 5+ messages in thread
From: Ulf Hansson @ 2020-08-21 12:25 UTC (permalink / raw)
  To: Ben Chuang
  Cc: Adrian Hunter, linux-mmc, Linux Kernel Mailing List, Ben Chuang,
	Takahiro Akashi, greg.tu

[...]

> > > @@ -2300,6 +2304,33 @@ void mmc_rescan(struct work_struct *work)
> > >                 goto out;
> > >         }
> > >
> > > +       if (host->caps & MMC_CAP_UHS2) {
> > > +               /*
> > > +                * Start to try UHS-II initialization from 52MHz to 26MHz
> > > +                * (RCLK range) per spec.
> > > +                */
> > > +               for (i = 0; i < ARRAY_SIZE(uhs2_freqs); i++) {
> > > +                       unsigned int freq = uhs2_freqs[i];
> > > +                       int err;
> > > +
> > > +                       err = mmc_uhs2_rescan_try_freq(host,
> > > +                                                      max(freq, host->f_min));
> > > +                       if (!err) {
> > > +                               mmc_release_host(host);
> > > +                               goto out;
> > > +                       }
> > > +
> > > +                       if (err == UHS2_PHY_INIT_ERR)
> > > +                               /* UHS2 IF detect or Lane Sync error.
> > > +                                * Try legacy interface.
> > > +                                */
> > > +                               break;
> > > +
> > > +                       if (freq <= host->f_min)
> > > +                               break;
> > > +               }
> >
> > Assuming we change the initialization order, trying to initialize the
> > legacy SD interface first to figure out if UHS-II is supported, then I
> > think we should be able to move the entire code above into a the
> > UHS-II specific code/path.
>
> If the host tries to use the SD interface first,
> some failure status needs to be considered.
>
> For example, first run in SD mode, try UHS-II interface failure,
>  and then return to SD flow again.
> I don't know a good way to go back to SD flow again.

Right, a re-try path for the legacy SD interface is a very good idea!
However, I don't think the initial support for UHS-II needs to cover
it. Instead we can add that on top, don't you think?

As a matter of fact, we could even use something like that for
different legacy SD speed modes. For example, if UHS-I SDR104 fails we
could try with UHS-I SDR25.

>
> >
> > > +       }
> > > +
> > >         for (i = 0; i < ARRAY_SIZE(freqs); i++) {
> > >                 unsigned int freq = freqs[i];
> > >                 if (freq > host->f_max) {
> > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> > > index 5a2210c25aa7..c5b071bd98b3 100644
> > > --- a/drivers/mmc/core/sd.c
> > > +++ b/drivers/mmc/core/sd.c
> > > @@ -901,6 +901,20 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
> > >                 err = mmc_read_switch(card);
> > >                 if (err)
> > >                         return err;
> > > +               if (host->flags & MMC_UHS2_INITIALIZED) {
> >
> > Rather than using host->flags, to tweak the behavior of
> > mmc_sd_setup_card() to support UHS-II, I would prefer to give
> > mmc_sd_setup_card() a new in-parameter that it can look at instead.
>
> Do you mean that adding a new in-parameter to mmc_sd_setup_card() likes this
> mmc_sd_setup_card(struct mmc_host *, struct mmc_card *, boot reinit,
> boot uhsii); ?

Correct.

[...]

Looks like we have covered most of the review for the mmc core
changes. But please tell me, if there is anything else you want me to
look at - at any time. Otherwise I am deferring to wait for a new
version of the series.

If I get some time, I may start to help with hacking some code.
Perhaps I can do some preparations, so it makes it easier for you to
add the UHS-II specific code. If so, I will let you know about it, of
course.

When it comes to the changes to SDHCI, I am relying on Adrian to give
his opinions.

Kind regards
Uffe

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface
  2020-08-21 12:25     ` Ulf Hansson
@ 2020-08-21 14:28       ` Adrian Hunter
  0 siblings, 0 replies; 5+ messages in thread
From: Adrian Hunter @ 2020-08-21 14:28 UTC (permalink / raw)
  To: Ulf Hansson, Ben Chuang
  Cc: linux-mmc, Linux Kernel Mailing List, Ben Chuang,
	Takahiro Akashi, greg.tu

On 21/08/20 3:25 pm, Ulf Hansson wrote:
> [...]
> 
>>>> @@ -2300,6 +2304,33 @@ void mmc_rescan(struct work_struct *work)
>>>>                 goto out;
>>>>         }
>>>>
>>>> +       if (host->caps & MMC_CAP_UHS2) {
>>>> +               /*
>>>> +                * Start to try UHS-II initialization from 52MHz to 26MHz
>>>> +                * (RCLK range) per spec.
>>>> +                */
>>>> +               for (i = 0; i < ARRAY_SIZE(uhs2_freqs); i++) {
>>>> +                       unsigned int freq = uhs2_freqs[i];
>>>> +                       int err;
>>>> +
>>>> +                       err = mmc_uhs2_rescan_try_freq(host,
>>>> +                                                      max(freq, host->f_min));
>>>> +                       if (!err) {
>>>> +                               mmc_release_host(host);
>>>> +                               goto out;
>>>> +                       }
>>>> +
>>>> +                       if (err == UHS2_PHY_INIT_ERR)
>>>> +                               /* UHS2 IF detect or Lane Sync error.
>>>> +                                * Try legacy interface.
>>>> +                                */
>>>> +                               break;
>>>> +
>>>> +                       if (freq <= host->f_min)
>>>> +                               break;
>>>> +               }
>>>
>>> Assuming we change the initialization order, trying to initialize the
>>> legacy SD interface first to figure out if UHS-II is supported, then I
>>> think we should be able to move the entire code above into a the
>>> UHS-II specific code/path.
>>
>> If the host tries to use the SD interface first,
>> some failure status needs to be considered.
>>
>> For example, first run in SD mode, try UHS-II interface failure,
>>  and then return to SD flow again.
>> I don't know a good way to go back to SD flow again.
> 
> Right, a re-try path for the legacy SD interface is a very good idea!
> However, I don't think the initial support for UHS-II needs to cover
> it. Instead we can add that on top, don't you think?
> 
> As a matter of fact, we could even use something like that for
> different legacy SD speed modes. For example, if UHS-I SDR104 fails we
> could try with UHS-I SDR25.
> 
>>
>>>
>>>> +       }
>>>> +
>>>>         for (i = 0; i < ARRAY_SIZE(freqs); i++) {
>>>>                 unsigned int freq = freqs[i];
>>>>                 if (freq > host->f_max) {
>>>> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
>>>> index 5a2210c25aa7..c5b071bd98b3 100644
>>>> --- a/drivers/mmc/core/sd.c
>>>> +++ b/drivers/mmc/core/sd.c
>>>> @@ -901,6 +901,20 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
>>>>                 err = mmc_read_switch(card);
>>>>                 if (err)
>>>>                         return err;
>>>> +               if (host->flags & MMC_UHS2_INITIALIZED) {
>>>
>>> Rather than using host->flags, to tweak the behavior of
>>> mmc_sd_setup_card() to support UHS-II, I would prefer to give
>>> mmc_sd_setup_card() a new in-parameter that it can look at instead.
>>
>> Do you mean that adding a new in-parameter to mmc_sd_setup_card() likes this
>> mmc_sd_setup_card(struct mmc_host *, struct mmc_card *, boot reinit,
>> boot uhsii); ?
> 
> Correct.
> 
> [...]
> 
> Looks like we have covered most of the review for the mmc core
> changes. But please tell me, if there is anything else you want me to
> look at - at any time. Otherwise I am deferring to wait for a new
> version of the series.
> 
> If I get some time, I may start to help with hacking some code.
> Perhaps I can do some preparations, so it makes it easier for you to
> add the UHS-II specific code. If so, I will let you know about it, of
> course.
> 
> When it comes to the changes to SDHCI, I am relying on Adrian to give
> his opinions.

I have made some comments.  The thrust of which is:
- get all the UHS-II code into sdhci-uhs2 (not sdhci.c)
- make the driver (i.e sdhci-pci-gli) set existing mmc host ops callbacks
and sdhci host ops callbacks as much as possible to provide UHS-II
functionality i.e. avoid adding new hooks if possible
- refactoring and exporting functions from sdhci.c where that can be done
logically, but otherwise writing separate code for UHS-II

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2020-08-21 14:28 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-10 11:08 [RFC PATCH V3 04/21] mmc: core: UHS-II support, try to select UHS-II interface Ben Chuang
2020-08-18 11:41 ` Ulf Hansson
2020-08-21 11:33   ` Ben Chuang
2020-08-21 12:25     ` Ulf Hansson
2020-08-21 14:28       ` Adrian Hunter

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