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mmc: sdhci: sdhci-pci-o2micro: Correctly set bus width when tuning

PATCH In review Raul E Rangel 3 participants 7 messages Jun 17, 2019 – Jun 18, 2019

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#0 lore raw

PATCH v2 1/3 mmc: sdhci: sdhci-pci-o2micro: Correctly set bus width when tuning

The O2Micro controller only supports tuning at 4-bits. So the host driver needs to change the bus width while tuning and then set it back when done.

There was a bug in the original implementation in that mmc->ios.bus_width also wasn't updated. Thus setting the incorrect blocksize in sdhci_send_tuning which results in a tuning failure.

Fixes 0086fc217d5d7 ("mmc: sdhci: Add support for O2 hardware tuning")

---

 drivers/mmc/host/sdhci-pci-o2micro.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
drivers/mmc/host/sdhci-pci-o2micro.c +4 -1
index b29bf4e7dcb48..dd21315922c87 100644
@@ -115,6 +115,7 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
 	 */
 	if (mmc->ios.bus_width == MMC_BUS_WIDTH_8) {
 		current_bus_width = mmc->ios.bus_width;
+		mmc->ios.bus_width = MMC_BUS_WIDTH_4;
 		sdhci_set_bus_width(host, MMC_BUS_WIDTH_4);
 	}
 
@@ -126,8 +127,10 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
 
 	sdhci_end_tuning(host);
 
-	if (current_bus_width == MMC_BUS_WIDTH_8)
+	if (current_bus_width == MMC_BUS_WIDTH_8) {
+		mmc->ios.bus_width = MMC_BUS_WIDTH_8;
 		sdhci_set_bus_width(host, current_bus_width);
+	}
 
 	host->flags &= ~SDHCI_HS400_TUNING;
 	return 0;
Signature · 1 line
2.22.0.410.gd8fdbe21b5-goog
#1 lore raw

PATCH v2 2/3 mmc: sdhci: sdhci-pci-o2micro: Check if controller supports 8-bit width

The O2 controller supports 8-bit EMMC access.

JESD84-B51 section A.6.3.a defines the bus testing procedure that mmc_select_bus_width() implements. This is used to determine the actual bus width of the eMMC.

---
I tested this on an AMD chromebook.

$ cat /sys/kernel/debug/mmc1/ios
clock:          200000000 Hz
actual clock:   200000000 Hz
vdd:            21 (3.3 ~ 3.4 V)
bus mode:       2 (push-pull)
chip select:    0 (don't care)
power mode:     2 (on)
bus width:      3 (8 bits)
timing spec:    9 (mmc HS200)
signal voltage: 1 (1.80 V)
driver type:    0 (driver type B)

Before this patch only 4 bit was negotiated.

 drivers/mmc/host/sdhci-pci-o2micro.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)
drivers/mmc/host/sdhci-pci-o2micro.c +11 -1
index dd21315922c87..9dc4548271b4b 100644
@@ -395,11 +395,21 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
 {
 	struct sdhci_pci_chip *chip;
 	struct sdhci_host *host;
-	u32 reg;
+	u32 reg, caps;
 	int ret;
 
 	chip = slot->chip;
 	host = slot->host;
+
+	caps = sdhci_readl(host, SDHCI_CAPABILITIES);
+
+	/*
+	 * mmc_select_bus_width() will test the bus to determine the actual bus
+	 * width.
+	 */
+	if (caps & SDHCI_CAN_DO_8BIT)
+		host->mmc->caps |= MMC_CAP_8_BIT_DATA;
+
 	switch (chip->pdev->device) {
 	case PCI_DEVICE_ID_O2_SDS0:
 	case PCI_DEVICE_ID_O2_SEABIRD0:
Signature · 1 line
2.22.0.410.gd8fdbe21b5-goog
maintainer Acked-by on v2 2/3
#2 lore raw

Re: [PATCH v2 2/3] mmc: sdhci: sdhci-pci-o2micro: Check if controller supports 8-bit width

Quoted 7 lines · Raul E Rangel

The O2 controller supports 8-bit EMMC access.

JESD84-B51 section A.6.3.a defines the bus testing procedure that mmc_select_bus_width() implements. This is used to determine the actual bus width of the eMMC.

Quoted 48 lines

---
I tested this on an AMD chromebook.

$ cat /sys/kernel/debug/mmc1/ios
clock:          200000000 Hz
actual clock:   200000000 Hz
vdd:            21 (3.3 ~ 3.4 V)
bus mode:       2 (push-pull)
chip select:    0 (don't care)
power mode:     2 (on)
bus width:      3 (8 bits)
timing spec:    9 (mmc HS200)
signal voltage: 1 (1.80 V)
driver type:    0 (driver type B)

Before this patch only 4 bit was negotiated.

 drivers/mmc/host/sdhci-pci-o2micro.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)
drivers/mmc/host/sdhci-pci-o2micro.c +11 -1
index dd21315922c87..9dc4548271b4b 100644
@@ -395,11 +395,21 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
 {
 	struct sdhci_pci_chip *chip;
 	struct sdhci_host *host;
-	u32 reg;
+	u32 reg, caps;
 	int ret;
 
 	chip = slot->chip;
 	host = slot->host;
+
+	caps = sdhci_readl(host, SDHCI_CAPABILITIES);
+
+	/*
+	 * mmc_select_bus_width() will test the bus to determine the actual bus
+	 * width.
+	 */
+	if (caps & SDHCI_CAN_DO_8BIT)
+		host->mmc->caps |= MMC_CAP_8_BIT_DATA;
+
 	switch (chip->pdev->device) {
 	case PCI_DEVICE_ID_O2_SDS0:
 	case PCI_DEVICE_ID_O2_SEABIRD0:
#3 lore raw

Re: [PATCH v2 2/3] mmc: sdhci: sdhci-pci-o2micro: Check if controller supports 8-bit width

In reply to Raul E Rangel
Quoted 8 lines · Raul E Rangel

The O2 controller supports 8-bit EMMC access.

JESD84-B51 section A.6.3.a defines the bus testing procedure that mmc_select_bus_width() implements. This is used to determine the actual bus width of the eMMC.

Applied for next, thanks!

Kind regards
Uffe

Quoted 50 lines

---
I tested this on an AMD chromebook.

$ cat /sys/kernel/debug/mmc1/ios
clock:          200000000 Hz
actual clock:   200000000 Hz
vdd:            21 (3.3 ~ 3.4 V)
bus mode:       2 (push-pull)
chip select:    0 (don't care)
power mode:     2 (on)
bus width:      3 (8 bits)
timing spec:    9 (mmc HS200)
signal voltage: 1 (1.80 V)
driver type:    0 (driver type B)

Before this patch only 4 bit was negotiated.

 drivers/mmc/host/sdhci-pci-o2micro.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)
drivers/mmc/host/sdhci-pci-o2micro.c +11 -2
index dd21315922c87..9dc4548271b4b 100644
@@ -395,11 +395,21 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
 {
        struct sdhci_pci_chip *chip;
        struct sdhci_host *host;
-       u32 reg;
+       u32 reg, caps;
        int ret;
 
        chip = slot->chip;
        host = slot->host;
+
+       caps = sdhci_readl(host, SDHCI_CAPABILITIES);
+
+       /*
+        * mmc_select_bus_width() will test the bus to determine the actual bus
+        * width.
+        */
+       if (caps & SDHCI_CAN_DO_8BIT)
+               host->mmc->caps |= MMC_CAP_8_BIT_DATA;
+
        switch (chip->pdev->device) {
        case PCI_DEVICE_ID_O2_SDS0:
        case PCI_DEVICE_ID_O2_SEABIRD0:
--

2.22.0.410.gd8fdbe21b5-goog

#4 lore raw

PATCH v2 3/3 mmc: sdhci: Fix indenting on SDHCI_CTRL_8BITBUS

In reply to Raul E Rangel

Remove whitespace in front of SDHCI_CTRL_8BITBUS. The value is not part of SDHCI_CTRL_DMA_MASK.

---

 drivers/mmc/host/sdhci.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/mmc/host/sdhci.h +1 -1
index 199712e7adbb3..89fd96596a1f7 100644
@@ -89,7 +89,7 @@
 #define   SDHCI_CTRL_ADMA32	0x10
 #define   SDHCI_CTRL_ADMA64	0x18
 #define   SDHCI_CTRL_ADMA3	0x18
-#define   SDHCI_CTRL_8BITBUS	0x20
+#define  SDHCI_CTRL_8BITBUS	0x20
 #define  SDHCI_CTRL_CDTEST_INS	0x40
 #define  SDHCI_CTRL_CDTEST_EN	0x80
 
Signature · 1 line
2.22.0.410.gd8fdbe21b5-goog
#5 lore raw

Re: [PATCH v2 3/3] mmc: sdhci: Fix indenting on SDHCI_CTRL_8BITBUS

Quoted 6 lines · Raul E Rangel

Remove whitespace in front of SDHCI_CTRL_8BITBUS. The value is not part of SDHCI_CTRL_DMA_MASK.

Applied for next, thanks!

Kind regards
Uffe

Quoted 21 lines

---

 drivers/mmc/host/sdhci.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/mmc/host/sdhci.h +1 -2
index 199712e7adbb3..89fd96596a1f7 100644
@@ -89,7 +89,7 @@
 #define   SDHCI_CTRL_ADMA32    0x10
 #define   SDHCI_CTRL_ADMA64    0x18
 #define   SDHCI_CTRL_ADMA3     0x18
-#define   SDHCI_CTRL_8BITBUS   0x20
+#define  SDHCI_CTRL_8BITBUS    0x20
 #define  SDHCI_CTRL_CDTEST_INS 0x40
 #define  SDHCI_CTRL_CDTEST_EN  0x80
 
--

2.22.0.410.gd8fdbe21b5-goog

#6 lore raw
In reply to Raul E Rangel
Quoted 11 lines · Raul E Rangel

The O2Micro controller only supports tuning at 4-bits. So the host driver needs to change the bus width while tuning and then set it back when done.

There was a bug in the original implementation in that mmc->ios.bus_width also wasn't updated. Thus setting the incorrect blocksize in sdhci_send_tuning which results in a tuning failure.

Fixes 0086fc217d5d7 ("mmc: sdhci: Add support for O2 hardware tuning")

Applied for fixes and by adding a stable tag, thanks!

Kind regards
Uffe

Quoted 32 lines

---

 drivers/mmc/host/sdhci-pci-o2micro.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
drivers/mmc/host/sdhci-pci-o2micro.c +4 -2
index b29bf4e7dcb48..dd21315922c87 100644
@@ -115,6 +115,7 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
         */
        if (mmc->ios.bus_width == MMC_BUS_WIDTH_8) {
                current_bus_width = mmc->ios.bus_width;
+               mmc->ios.bus_width = MMC_BUS_WIDTH_4;
                sdhci_set_bus_width(host, MMC_BUS_WIDTH_4);
        }
 
@@ -126,8 +127,10 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
 
        sdhci_end_tuning(host);
 
-       if (current_bus_width == MMC_BUS_WIDTH_8)
+       if (current_bus_width == MMC_BUS_WIDTH_8) {
+               mmc->ios.bus_width = MMC_BUS_WIDTH_8;
                sdhci_set_bus_width(host, current_bus_width);
+       }
 
        host->flags &= ~SDHCI_HS400_TUNING;
        return 0;
--

2.22.0.410.gd8fdbe21b5-goog