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Diffstat (limited to 'meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0029-i2c-aspeed-Improve-driver-to-support-multi-master-us.patch')
-rw-r--r--meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0029-i2c-aspeed-Improve-driver-to-support-multi-master-us.patch291
1 files changed, 0 insertions, 291 deletions
diff --git a/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0029-i2c-aspeed-Improve-driver-to-support-multi-master-us.patch b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0029-i2c-aspeed-Improve-driver-to-support-multi-master-us.patch
deleted file mode 100644
index e2dee0d5b..000000000
--- a/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/0029-i2c-aspeed-Improve-driver-to-support-multi-master-us.patch
+++ /dev/null
@@ -1,291 +0,0 @@
-From a7ad8d09cdf0ec86612df0714d3e69ee92e6140b Mon Sep 17 00:00:00 2001
-From: Jae Hyun Yoo <jae.hyun.yoo@intel.com>
-Date: Tue, 20 Nov 2018 09:30:17 -0800
-Subject: [PATCH] i2c: aspeed: Improve driver to support multi-master use cases
- stably
-
-In multi-master environment, this driver's master cannot know
-exactly when peer master sends data to this driver's slave so
-cases can be happened that this master tries to send data through
-the master_xfer function but slave data from a peer master is still
-being processed or slave xfer is started by a peer very after it
-queues a master command.
-
-To prevent state corruption in these cases, this patch adds the
-'pending' state of master and its handling code so that the pending
-master xfer can be continued after slave mode session.
-
-Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
----
- drivers/i2c/busses/i2c-aspeed.c | 119 ++++++++++++++++++++++++++++++----------
- 1 file changed, 91 insertions(+), 28 deletions(-)
-
-diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
-index 8dc9161ced38..d11b2ea97259 100644
---- a/drivers/i2c/busses/i2c-aspeed.c
-+++ b/drivers/i2c/busses/i2c-aspeed.c
-@@ -117,6 +117,7 @@
-
- enum aspeed_i2c_master_state {
- ASPEED_I2C_MASTER_INACTIVE,
-+ ASPEED_I2C_MASTER_PENDING,
- ASPEED_I2C_MASTER_START,
- ASPEED_I2C_MASTER_TX_FIRST,
- ASPEED_I2C_MASTER_TX,
-@@ -126,12 +127,13 @@ enum aspeed_i2c_master_state {
- };
-
- enum aspeed_i2c_slave_state {
-- ASPEED_I2C_SLAVE_STOP,
-+ ASPEED_I2C_SLAVE_INACTIVE,
- ASPEED_I2C_SLAVE_START,
- ASPEED_I2C_SLAVE_READ_REQUESTED,
- ASPEED_I2C_SLAVE_READ_PROCESSED,
- ASPEED_I2C_SLAVE_WRITE_REQUESTED,
- ASPEED_I2C_SLAVE_WRITE_RECEIVED,
-+ ASPEED_I2C_SLAVE_STOP,
- };
-
- struct aspeed_i2c_bus {
-@@ -156,6 +158,8 @@ struct aspeed_i2c_bus {
- int cmd_err;
- /* Protected only by i2c_lock_bus */
- int master_xfer_result;
-+ /* Multi-master */
-+ bool multi_master;
- #if IS_ENABLED(CONFIG_I2C_SLAVE)
- struct i2c_client *slave;
- enum aspeed_i2c_slave_state slave_state;
-@@ -251,7 +255,7 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- }
-
- /* Slave is not currently active, irq was for someone else. */
-- if (bus->slave_state == ASPEED_I2C_SLAVE_STOP)
-+ if (bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE)
- return irq_handled;
-
- dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n",
-@@ -277,16 +281,15 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
- bus->slave_state = ASPEED_I2C_SLAVE_STOP;
- }
-- if (irq_status & ASPEED_I2CD_INTR_TX_NAK) {
-+ if (irq_status & ASPEED_I2CD_INTR_TX_NAK &&
-+ bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) {
- irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
- bus->slave_state = ASPEED_I2C_SLAVE_STOP;
- }
-- if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
-- irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
-
- switch (bus->slave_state) {
- case ASPEED_I2C_SLAVE_READ_REQUESTED:
-- if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
-+ if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_ACK))
- dev_err(bus->dev, "Unexpected ACK on read request.\n");
- bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED;
- i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
-@@ -294,9 +297,12 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG);
- break;
- case ASPEED_I2C_SLAVE_READ_PROCESSED:
-- if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK))
-+ if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
- dev_err(bus->dev,
- "Expected ACK after processed read.\n");
-+ break;
-+ }
-+ irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
- i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value);
- writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG);
- writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG);
-@@ -310,10 +316,15 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- break;
- case ASPEED_I2C_SLAVE_STOP:
- i2c_slave_event(slave, I2C_SLAVE_STOP, &value);
-+ bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
-+ break;
-+ case ASPEED_I2C_SLAVE_START:
-+ /* Slave was just started. Waiting for the next event. */;
- break;
- default:
-- dev_err(bus->dev, "unhandled slave_state: %d\n",
-+ dev_err(bus->dev, "unknown slave_state: %d\n",
- bus->slave_state);
-+ bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
- break;
- }
-
-@@ -328,7 +339,17 @@ static void aspeed_i2c_do_start(struct aspeed_i2c_bus *bus)
- struct i2c_msg *msg = &bus->msgs[bus->msgs_index];
- u8 slave_addr = i2c_8bit_addr_from_msg(msg);
-
-- bus->master_state = ASPEED_I2C_MASTER_START;
-+#if IS_ENABLED(CONFIG_I2C_SLAVE)
-+ /*
-+ * If it's requested in the middle of a slave session, set the master
-+ * state to 'pending' then H/W will continue handling this master
-+ * command when the bus comes back to idle state.
-+ */
-+ if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE)
-+ bus->master_state = ASPEED_I2C_MASTER_PENDING;
-+ else
-+#endif /* CONFIG_I2C_SLAVE */
-+ bus->master_state = ASPEED_I2C_MASTER_START;
- bus->buf_index = 0;
-
- if (msg->flags & I2C_M_RD) {
-@@ -384,10 +405,6 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
- irq_handled |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE;
- goto out_complete;
-- } else {
-- /* Master is not currently active, irq was for someone else. */
-- if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE)
-- goto out_no_complete;
- }
-
- /*
-@@ -399,12 +416,33 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- if (ret) {
- dev_dbg(bus->dev, "received error interrupt: 0x%08x\n",
- irq_status);
-- bus->cmd_err = ret;
-- bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
- irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_ERRORS);
-- goto out_complete;
-+ if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
-+ bus->cmd_err = ret;
-+ bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
-+ goto out_complete;
-+ }
- }
-
-+#if IS_ENABLED(CONFIG_I2C_SLAVE)
-+ /*
-+ * A pending master command will be started by H/W when the bus comes
-+ * back to idle state after completing a slave operation so change the
-+ * master state from 'pending' to 'start' at here if slave is inactive.
-+ */
-+ if (bus->master_state == ASPEED_I2C_MASTER_PENDING) {
-+ if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE)
-+ goto out_no_complete;
-+
-+ bus->master_state = ASPEED_I2C_MASTER_START;
-+ }
-+#endif /* CONFIG_I2C_SLAVE */
-+
-+ /* Master is not currently active, irq was for someone else. */
-+ if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE ||
-+ bus->master_state == ASPEED_I2C_MASTER_PENDING)
-+ goto out_no_complete;
-+
- /* We are in an invalid state; reset bus to a known state. */
- if (!bus->msgs) {
- dev_err(bus->dev, "bus in unknown state. irq_status: 0x%x\n",
-@@ -423,6 +461,20 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
- * then update the state and handle the new state below.
- */
- if (bus->master_state == ASPEED_I2C_MASTER_START) {
-+#if IS_ENABLED(CONFIG_I2C_SLAVE)
-+ /*
-+ * If a peer master starts a xfer very after it queues a master
-+ * command, change its state to 'pending' then H/W will continue
-+ * the queued master xfer just after completing the slave mode
-+ * session.
-+ */
-+ if (unlikely(irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH)) {
-+ bus->master_state = ASPEED_I2C_MASTER_PENDING;
-+ dev_dbg(bus->dev,
-+ "master goes pending due to a slave start\n");
-+ goto out_no_complete;
-+ }
-+#endif /* CONFIG_I2C_SLAVE */
- if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
- if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_NAK))) {
- bus->cmd_err = -ENXIO;
-@@ -566,7 +618,8 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
- * interrupt bits. Each case needs to be handled using corresponding
- * handlers depending on the current state.
- */
-- if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
-+ if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE &&
-+ bus->master_state != ASPEED_I2C_MASTER_PENDING) {
- irq_handled = aspeed_i2c_master_irq(bus, irq_remaining);
- irq_remaining &= ~irq_handled;
- if (irq_remaining)
-@@ -601,15 +654,14 @@ static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
- {
- struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap);
- unsigned long time_left, flags;
-- int ret = 0;
-+ int ret;
-
- spin_lock_irqsave(&bus->lock, flags);
- bus->cmd_err = 0;
-
-- /* If bus is busy, attempt recovery. We assume a single master
-- * environment.
-- */
-- if (readl(bus->base + ASPEED_I2C_CMD_REG) & ASPEED_I2CD_BUS_BUSY_STS) {
-+ /* If bus is busy in a single master environment, attempt recovery. */
-+ if (!bus->multi_master &&
-+ (readl(bus->base + ASPEED_I2C_CMD_REG) & ASPEED_I2CD_BUS_BUSY_STS)) {
- spin_unlock_irqrestore(&bus->lock, flags);
- ret = aspeed_i2c_recover_bus(bus);
- if (ret)
-@@ -629,10 +681,20 @@ static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
- time_left = wait_for_completion_timeout(&bus->cmd_complete,
- bus->adap.timeout);
-
-- if (time_left == 0)
-+ if (time_left == 0) {
-+ /*
-+ * If timed out and bus is still busy in a multi master
-+ * environment, attempt recovery at here.
-+ */
-+ if (bus->multi_master &&
-+ (readl(bus->base + ASPEED_I2C_CMD_REG) &
-+ ASPEED_I2CD_BUS_BUSY_STS))
-+ ret = aspeed_i2c_recover_bus(bus);
-+
- return -ETIMEDOUT;
-- else
-- return bus->master_xfer_result;
-+ }
-+
-+ return bus->master_xfer_result;
- }
-
- static u32 aspeed_i2c_functionality(struct i2c_adapter *adap)
-@@ -672,7 +734,7 @@ static int aspeed_i2c_reg_slave(struct i2c_client *client)
- __aspeed_i2c_reg_slave(bus, client->addr);
-
- bus->slave = client;
-- bus->slave_state = ASPEED_I2C_SLAVE_STOP;
-+ bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
- spin_unlock_irqrestore(&bus->lock, flags);
-
- return 0;
-@@ -827,7 +889,9 @@ static int aspeed_i2c_init(struct aspeed_i2c_bus *bus,
- if (ret < 0)
- return ret;
-
-- if (!of_property_read_bool(pdev->dev.of_node, "multi-master"))
-+ if (of_property_read_bool(pdev->dev.of_node, "multi-master"))
-+ bus->multi_master = true;
-+ else
- fun_ctrl_reg |= ASPEED_I2CD_MULTI_MASTER_DIS;
-
- /* Enable Master Mode */
-@@ -930,7 +994,6 @@ static int aspeed_i2c_probe_bus(struct platform_device *pdev)
- init_completion(&bus->cmd_complete);
- bus->adap.owner = THIS_MODULE;
- bus->adap.retries = 0;
-- bus->adap.timeout = 5 * HZ;
- bus->adap.algo = &aspeed_i2c_algo;
- bus->adap.dev.parent = &pdev->dev;
- bus->adap.dev.of_node = pdev->dev.of_node;
---
-2.7.4
-
generated by cgit v1.2.3 (git 2.39.0) at 2024-08-25 22:31:46 +0300