mmc: Change mode when switching to a boot partition

Boot partitions do not support HS200. Changing to a lower performance mode is required to access them. mmc_select_mode_and_width() and sd_select_mode_and_width() are modified to make it easier to call them outside of the initialization context. Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> Reviewed-by: Simon Glass <sjg@chromium.org>

mmc: Change mode when switching to a boot partition
Boot partitions do not support HS200. Changing to a lower performance mode is required to access them. mmc_select_mode_and_width() and sd_select_mode_and_width() are modified to make it easier to call them outside of the initialization context. Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> Reviewed-by: Simon Glass <sjg@chromium.org>
Jean-Jacques Hiblot · Jaehoon Chung · Eric Lee · Eric Lee · Eric Lee · Eric Lee
1 parent 04a2ea248f
Showing 2 changed files with 55 additions and 18 deletions Side-by-side Diff
drivers/mmc/mmc.c
include/mmc.h
@@ -32,6 +32,7 @@
  
 static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage);
 static int mmc_power_cycle(struct mmc *mmc);
+static int mmc_select_mode_and_width(struct mmc *mmc, uint card_caps);
  
 #if CONFIG_IS_ENABLED(MMC_TINY)
 static struct mmc mmc_static;
  
@@ -792,10 +793,38 @@
 	return 0;
 }
  
+static int mmc_boot_part_access_chk(struct mmc *mmc, unsigned int part_num)
+{
+	int forbidden = 0;
+	bool change = false;
+
+	if (part_num & PART_ACCESS_MASK)
+		forbidden = MMC_CAP(MMC_HS_200);
+
+	if (MMC_CAP(mmc->selected_mode) & forbidden) {
+		debug("selected mode (%s) is forbidden for part %d\n",
+		      mmc_mode_name(mmc->selected_mode), part_num);
+		change = true;
+	} else if (mmc->selected_mode != mmc->best_mode) {
+		debug("selected mode is not optimal\n");
+		change = true;
+	}
+
+	if (change)
+		return mmc_select_mode_and_width(mmc,
+						 mmc->card_caps & ~forbidden);
+
+	return 0;
+}
+
 int mmc_switch_part(struct mmc *mmc, unsigned int part_num)
 {
 	int ret;
  
+	ret = mmc_boot_part_access_chk(mmc, part_num);
+	if (ret)
+		return ret;
+
 	ret = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_PART_CONF,
 			 (mmc->part_config & ~PART_ACCESS_MASK)
 			 | (part_num & PART_ACCESS_MASK));
@@ -1438,7 +1467,7 @@
 	     mwt++) \
 		if (caps & MMC_CAP(mwt->mode))
  
-static int sd_select_mode_and_width(struct mmc *mmc)
+static int sd_select_mode_and_width(struct mmc *mmc, uint card_caps)
 {
 	int err;
 	uint widths[] = {MMC_MODE_4BIT, MMC_MODE_1BIT};
  
@@ -1447,11 +1476,8 @@
 	uint caps;
  
  
-	err = sd_get_capabilities(mmc);
-	if (err)
-		return err;
 	/* Restrict card's capabilities by what the host can do */
-	caps = mmc->card_caps & (mmc->host_caps | MMC_MODE_1BIT);
+	caps = card_caps & (mmc->host_caps | MMC_MODE_1BIT);
  
 	if (!uhs_en)
 		caps &= ~UHS_CAPS;
  
  
@@ -1588,18 +1614,14 @@
 	    ecbv++) \
 		if ((ddr == ecbv->is_ddr) && (caps & ecbv->cap))
  
-static int mmc_select_mode_and_width(struct mmc *mmc)
+static int mmc_select_mode_and_width(struct mmc *mmc, uint card_caps)
 {
 	int err;
 	const struct mode_width_tuning *mwt;
 	const struct ext_csd_bus_width *ecbw;
  
-	err = mmc_get_capabilities(mmc);
-	if (err)
-		return err;
-
 	/* Restrict card's capabilities by what the host can do */
-	mmc->card_caps &= (mmc->host_caps | MMC_MODE_1BIT);
+	card_caps &= (mmc->host_caps | MMC_MODE_1BIT);
  
 	/* Only version 4 of MMC supports wider bus widths */
 	if (mmc->version < MMC_VERSION_4)
@@ -1610,8 +1632,10 @@
 		return -ENOTSUPP;
 	}
  
-	for_each_mmc_mode_by_pref(mmc->card_caps, mwt) {
-		for_each_supported_width(mmc->card_caps & mwt->widths,
+	mmc_set_clock(mmc, mmc->legacy_speed, false);
+
+	for_each_mmc_mode_by_pref(card_caps, mwt) {
+		for_each_supported_width(card_caps & mwt->widths,
 					 mmc_is_mode_ddr(mwt->mode), ecbw) {
 			debug("trying mode %s width %d (at %d MHz)\n",
 			      mmc_mode_name(mwt->mode),
  
@@ -2006,14 +2030,22 @@
 	if (err)
 		return err;
  
-	if (IS_SD(mmc))
-		err = sd_select_mode_and_width(mmc);
-	else
-		err = mmc_select_mode_and_width(mmc);
+	if (IS_SD(mmc)) {
+		err = sd_get_capabilities(mmc);
+		if (err)
+			return err;
+		err = sd_select_mode_and_width(mmc, mmc->card_caps);
+	} else {
+		err = mmc_get_capabilities(mmc);
+		if (err)
+			return err;
+		mmc_select_mode_and_width(mmc, mmc->card_caps);
+	}
  
 	if (err)
 		return err;
  
+	mmc->best_mode = mmc->selected_mode;
  
 	/* Fix the block length for DDR mode */
 	if (mmc->ddr_mode) {
@@ -585,7 +585,12 @@
 #endif
 #endif
 	u8 *ext_csd;
-	enum bus_mode selected_mode;
+	enum bus_mode selected_mode; /* mode currently used */
+	enum bus_mode best_mode; /* best mode is the supported mode with the
+				  * highest bandwidth. It may not always be the
+				  * operating mode due to limitations when
+				  * accessing the boot partitions
+				  */
 };
  
 struct mmc_hwpart_conf {
...	...	@@ -32,6 +32,7 @@
32	32
33	33	static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage);
34	34	static int mmc_power_cycle(struct mmc *mmc);
	35	+static int mmc_select_mode_and_width(struct mmc *mmc, uint card_caps);
35	36
36	37	#if CONFIG_IS_ENABLED(MMC_TINY)
37	38	static struct mmc mmc_static;
38	39
...	...	@@ -792,10 +793,38 @@
792	793	return 0;
793	794	}
794	795
	796	+static int mmc_boot_part_access_chk(struct mmc *mmc, unsigned int part_num)
	797	+{
	798	+ int forbidden = 0;
	799	+ bool change = false;
	800	+
	801	+ if (part_num & PART_ACCESS_MASK)
	802	+ forbidden = MMC_CAP(MMC_HS_200);
	803	+
	804	+ if (MMC_CAP(mmc->selected_mode) & forbidden) {
	805	+ debug("selected mode (%s) is forbidden for part %d\n",
	806	+ mmc_mode_name(mmc->selected_mode), part_num);
	807	+ change = true;
	808	+ } else if (mmc->selected_mode != mmc->best_mode) {
	809	+ debug("selected mode is not optimal\n");
	810	+ change = true;
	811	+ }
	812	+
	813	+ if (change)
	814	+ return mmc_select_mode_and_width(mmc,
	815	+ mmc->card_caps & ~forbidden);
	816	+
	817	+ return 0;
	818	+}
	819	+
795	820	int mmc_switch_part(struct mmc *mmc, unsigned int part_num)
796	821	{
797	822	int ret;
798	823
	824	+ ret = mmc_boot_part_access_chk(mmc, part_num);
	825	+ if (ret)
	826	+ return ret;
	827	+
799	828	ret = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_PART_CONF,
800	829	(mmc->part_config & ~PART_ACCESS_MASK)
801	830	\| (part_num & PART_ACCESS_MASK));
...	...	@@ -1438,7 +1467,7 @@
1438	1467	mwt++) \
1439	1468	if (caps & MMC_CAP(mwt->mode))
1440	1469
1441		-static int sd_select_mode_and_width(struct mmc *mmc)
	1470	+static int sd_select_mode_and_width(struct mmc *mmc, uint card_caps)
1442	1471	{
1443	1472	int err;
1444	1473	uint widths[] = {MMC_MODE_4BIT, MMC_MODE_1BIT};
1445	1474
...	...	@@ -1447,11 +1476,8 @@
1447	1476	uint caps;
1448	1477
1449	1478
1450		- err = sd_get_capabilities(mmc);
1451		- if (err)
1452		- return err;
1453	1479	/* Restrict card's capabilities by what the host can do */
1454		- caps = mmc->card_caps & (mmc->host_caps \| MMC_MODE_1BIT);
	1480	+ caps = card_caps & (mmc->host_caps \| MMC_MODE_1BIT);
1455	1481
1456	1482	if (!uhs_en)
1457	1483	caps &= ~UHS_CAPS;
1458	1484
1459	1485
...	...	@@ -1588,18 +1614,14 @@
1588	1614	ecbv++) \
1589	1615	if ((ddr == ecbv->is_ddr) && (caps & ecbv->cap))
1590	1616
1591		-static int mmc_select_mode_and_width(struct mmc *mmc)
	1617	+static int mmc_select_mode_and_width(struct mmc *mmc, uint card_caps)
1592	1618	{
1593	1619	int err;
1594	1620	const struct mode_width_tuning *mwt;
1595	1621	const struct ext_csd_bus_width *ecbw;
1596	1622
1597		- err = mmc_get_capabilities(mmc);
1598		- if (err)
1599		- return err;
1600		-
1601	1623	/* Restrict card's capabilities by what the host can do */
1602		- mmc->card_caps &= (mmc->host_caps \| MMC_MODE_1BIT);
	1624	+ card_caps &= (mmc->host_caps \| MMC_MODE_1BIT);
1603	1625
1604	1626	/* Only version 4 of MMC supports wider bus widths */
1605	1627	if (mmc->version < MMC_VERSION_4)
...	...	@@ -1610,8 +1632,10 @@
1610	1632	return -ENOTSUPP;
1611	1633	}
1612	1634
1613		- for_each_mmc_mode_by_pref(mmc->card_caps, mwt) {
1614		- for_each_supported_width(mmc->card_caps & mwt->widths,
	1635	+ mmc_set_clock(mmc, mmc->legacy_speed, false);
	1636	+
	1637	+ for_each_mmc_mode_by_pref(card_caps, mwt) {
	1638	+ for_each_supported_width(card_caps & mwt->widths,
1615	1639	mmc_is_mode_ddr(mwt->mode), ecbw) {
1616	1640	debug("trying mode %s width %d (at %d MHz)\n",
1617	1641	mmc_mode_name(mwt->mode),
1618	1642
...	...	@@ -2006,14 +2030,22 @@
2006	2030	if (err)
2007	2031	return err;
2008	2032
2009		- if (IS_SD(mmc))
2010		- err = sd_select_mode_and_width(mmc);
2011		- else
2012		- err = mmc_select_mode_and_width(mmc);
	2033	+ if (IS_SD(mmc)) {
	2034	+ err = sd_get_capabilities(mmc);
	2035	+ if (err)
	2036	+ return err;
	2037	+ err = sd_select_mode_and_width(mmc, mmc->card_caps);
	2038	+ } else {
	2039	+ err = mmc_get_capabilities(mmc);
	2040	+ if (err)
	2041	+ return err;
	2042	+ mmc_select_mode_and_width(mmc, mmc->card_caps);
	2043	+ }
2013	2044
2014	2045	if (err)
2015	2046	return err;
2016	2047
	2048	+ mmc->best_mode = mmc->selected_mode;
2017	2049
2018	2050	/* Fix the block length for DDR mode */
2019	2051	if (mmc->ddr_mode) {
...	...	@@ -585,7 +585,12 @@
585	585	#endif
586	586	#endif
587	587	u8 *ext_csd;
588		- enum bus_mode selected_mode;
	588	+ enum bus_mode selected_mode; /* mode currently used */
	589	+ enum bus_mode best_mode; /* best mode is the supported mode with the
	590	+ * highest bandwidth. It may not always be the
	591	+ * operating mode due to limitations when
	592	+ * accessing the boot partitions
	593	+ */
589	594	};
590	595
591	596	struct mmc_hwpart_conf {