[PATCH AUTOSEL 5.11 057/104] mt76: mt7915: add wifi subsystem reset

From: Sasha Levin
Date: Wed May 05 2021 - 12:49:58 EST


From: Ryder Lee <ryder.lee@xxxxxxxxxxxx>

[ Upstream commit e07419a7dca97dd9bddfe5d099380857c19535f3 ]

Reset wifi subsystem when MCU is already running.
Fixes firmware download failure after soft reboot on systems where the PCIe
reset could not be performed properly.

Signed-off-by: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
Co-developed-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../net/wireless/mediatek/mt76/mt7915/init.c | 58 ++++++++++++++++++-
.../net/wireless/mediatek/mt76/mt7915/mcu.c | 15 +----
.../net/wireless/mediatek/mt76/mt7915/regs.h | 13 +++++
3 files changed, 70 insertions(+), 16 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/init.c b/drivers/net/wireless/mediatek/mt76/mt7915/init.c
index 2ec18aaa8280..aaa8006e0950 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/init.c
@@ -4,6 +4,7 @@
#include <linux/etherdevice.h>
#include "mt7915.h"
#include "mac.h"
+#include "mcu.h"
#include "eeprom.h"

#define CCK_RATE(_idx, _rate) { \
@@ -282,9 +283,50 @@ static void mt7915_init_work(struct work_struct *work)
mt7915_register_ext_phy(dev);
}

+static void mt7915_wfsys_reset(struct mt7915_dev *dev)
+{
+ u32 val = MT_TOP_PWR_KEY | MT_TOP_PWR_SW_PWR_ON | MT_TOP_PWR_PWR_ON;
+ u32 reg = mt7915_reg_map_l1(dev, MT_TOP_MISC);
+
+#define MT_MCU_DUMMY_RANDOM GENMASK(15, 0)
+#define MT_MCU_DUMMY_DEFAULT GENMASK(31, 16)
+
+ mt76_wr(dev, MT_MCU_WFDMA0_DUMMY_CR, MT_MCU_DUMMY_RANDOM);
+
+ /* change to software control */
+ val |= MT_TOP_PWR_SW_RST;
+ mt76_wr(dev, MT_TOP_PWR_CTRL, val);
+
+ /* reset wfsys */
+ val &= ~MT_TOP_PWR_SW_RST;
+ mt76_wr(dev, MT_TOP_PWR_CTRL, val);
+
+ /* release wfsys then mcu re-excutes romcode */
+ val |= MT_TOP_PWR_SW_RST;
+ mt76_wr(dev, MT_TOP_PWR_CTRL, val);
+
+ /* switch to hw control */
+ val &= ~MT_TOP_PWR_SW_RST;
+ val |= MT_TOP_PWR_HW_CTRL;
+ mt76_wr(dev, MT_TOP_PWR_CTRL, val);
+
+ /* check whether mcu resets to default */
+ if (!mt76_poll_msec(dev, MT_MCU_WFDMA0_DUMMY_CR, MT_MCU_DUMMY_DEFAULT,
+ MT_MCU_DUMMY_DEFAULT, 1000)) {
+ dev_err(dev->mt76.dev, "wifi subsystem reset failure\n");
+ return;
+ }
+
+ /* wfsys reset won't clear host registers */
+ mt76_clear(dev, reg, MT_TOP_MISC_FW_STATE);
+
+ msleep(100);
+}
+
static int mt7915_init_hardware(struct mt7915_dev *dev)
{
int ret, idx;
+ u32 val;

mt76_wr(dev, MT_INT_SOURCE_CSR, ~0);

@@ -294,6 +336,12 @@ static int mt7915_init_hardware(struct mt7915_dev *dev)

dev->dbdc_support = !!(mt7915_l1_rr(dev, MT_HW_BOUND) & BIT(5));

+ val = mt76_rr(dev, mt7915_reg_map_l1(dev, MT_TOP_MISC));
+
+ /* If MCU was already running, it is likely in a bad state */
+ if (FIELD_GET(MT_TOP_MISC_FW_STATE, val) > FW_STATE_FW_DOWNLOAD)
+ mt7915_wfsys_reset(dev);
+
ret = mt7915_dma_init(dev);
if (ret)
return ret;
@@ -307,8 +355,14 @@ static int mt7915_init_hardware(struct mt7915_dev *dev)
mt76_wr(dev, MT_SWDEF_MODE, MT_SWDEF_NORMAL_MODE);

ret = mt7915_mcu_init(dev);
- if (ret)
- return ret;
+ if (ret) {
+ /* Reset and try again */
+ mt7915_wfsys_reset(dev);
+
+ ret = mt7915_mcu_init(dev);
+ if (ret)
+ return ret;
+ }

ret = mt7915_eeprom_init(dev);
if (ret < 0)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
index 1cbae0eacfe9..a0aa76ac16b9 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
@@ -2780,21 +2780,8 @@ static int mt7915_load_ram(struct mt7915_dev *dev)

static int mt7915_load_firmware(struct mt7915_dev *dev)
{
+ u32 reg = mt7915_reg_map_l1(dev, MT_TOP_MISC);
int ret;
- u32 val, reg = mt7915_reg_map_l1(dev, MT_TOP_MISC);
-
- val = FIELD_PREP(MT_TOP_MISC_FW_STATE, FW_STATE_FW_DOWNLOAD);
-
- if (!mt76_poll_msec(dev, reg, MT_TOP_MISC_FW_STATE, val, 1000)) {
- /* restart firmware once */
- __mt76_mcu_restart(&dev->mt76);
- if (!mt76_poll_msec(dev, reg, MT_TOP_MISC_FW_STATE,
- val, 1000)) {
- dev_err(dev->mt76.dev,
- "Firmware is not ready for download\n");
- return -EIO;
- }
- }

ret = mt7915_load_patch(dev);
if (ret)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/regs.h b/drivers/net/wireless/mediatek/mt76/mt7915/regs.h
index 848703e6eb7c..8a0ceb30392c 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/regs.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/regs.h
@@ -4,6 +4,11 @@
#ifndef __MT7915_REGS_H
#define __MT7915_REGS_H

+/* MCU WFDMA0 */
+#define MT_MCU_WFDMA0_BASE 0x2000
+#define MT_MCU_WFDMA0(ofs) (MT_MCU_WFDMA0_BASE + (ofs))
+#define MT_MCU_WFDMA0_DUMMY_CR MT_MCU_WFDMA0(0x120)
+
/* MCU WFDMA1 */
#define MT_MCU_WFDMA1_BASE 0x3000
#define MT_MCU_WFDMA1(ofs) (MT_MCU_WFDMA1_BASE + (ofs))
@@ -375,6 +380,14 @@
#define MT_WFDMA1_PCIE1_BUSY_ENA_TX_FIFO1 BIT(1)
#define MT_WFDMA1_PCIE1_BUSY_ENA_RX_FIFO BIT(2)

+#define MT_TOP_RGU_BASE 0xf0000
+#define MT_TOP_PWR_CTRL (MT_TOP_RGU_BASE + (0x0))
+#define MT_TOP_PWR_KEY (0x5746 << 16)
+#define MT_TOP_PWR_SW_RST BIT(0)
+#define MT_TOP_PWR_SW_PWR_ON GENMASK(3, 2)
+#define MT_TOP_PWR_HW_CTRL BIT(4)
+#define MT_TOP_PWR_PWR_ON BIT(7)
+
#define MT_INFRA_CFG_BASE 0xf1000
#define MT_INFRA(ofs) (MT_INFRA_CFG_BASE + (ofs))

--
2.30.2