Store DMA mapping data in geni_i2c_dev struct. Implement Shutdown callback for geni i2c driver.
Changes in V2: - Changed commit text. - As per Stephen's comments added separate function for stop transfer.
Roja Rani Yarubandi (2): i2c: i2c-qcom-geni: Store DMA mapping data in geni_i2c_dev struct i2c: i2c-qcom-geni: Add shutdown callback for i2c
drivers/i2c/busses/i2c-qcom-geni.c | 50 ++++++++++++++++++++++++++++++ include/linux/qcom-geni-se.h | 5 +++ 2 files changed, 55 insertions(+)
Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping data scope. For example during shutdown callback to unmap DMA mapping, this stored DMA mapping data can be used to call geni_se_tx_dma_unprep and geni_se_rx_dma_unprep functions.
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org --- Changes in V2: - As per Stephen's comments, changed commit text, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 7f130829bf01..1fda5c7c2cfc 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -86,6 +86,9 @@ struct geni_i2c_dev { u32 clk_freq_out; const struct geni_i2c_clk_fld *clk_fld; int suspended; + dma_addr_t tx_dma; + dma_addr_t rx_dma; + size_t xfer_len; };
struct geni_i2c_err_log { @@ -358,6 +361,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, struct geni_se *se = &gi2c->se; size_t len = msg->len;
+ gi2c->xfer_len = msg->len; if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
@@ -384,6 +388,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_rx_fsm_rst(gi2c); + gi2c->rx_dma = rx_dma; geni_se_rx_dma_unprep(se, rx_dma, len); i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); } @@ -400,6 +405,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, struct geni_se *se = &gi2c->se; size_t len = msg->len;
+ gi2c->xfer_len = msg->len; if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
@@ -429,6 +435,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_tx_fsm_rst(gi2c); + gi2c->tx_dma = tx_dma; geni_se_tx_dma_unprep(se, tx_dma, len); i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); }
Quoting Roja Rani Yarubandi (2020-08-20 03:35:21)
Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping data scope. For example during shutdown callback to unmap DMA mapping, this stored DMA mapping data can be used to call geni_se_tx_dma_unprep and geni_se_rx_dma_unprep functions.
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
Can this be squashed with the next patch? I don't see how this stands on its own.
On 2020-08-21 05:48, Stephen Boyd wrote:
Quoting Roja Rani Yarubandi (2020-08-20 03:35:21)
Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping data scope. For example during shutdown callback to unmap DMA mapping, this stored DMA mapping data can be used to call geni_se_tx_dma_unprep and geni_se_rx_dma_unprep functions.
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
Can this be squashed with the next patch? I don't see how this stands on its own.
Okay.
Hi Roja,
On 8/20/2020 4:05 PM, Roja Rani Yarubandi wrote:
Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping data scope. For example during shutdown callback to unmap DMA mapping, this stored DMA mapping data can be used to call geni_se_tx_dma_unprep and geni_se_rx_dma_unprep functions.
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
Changes in V2:
- As per Stephen's comments, changed commit text, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 7f130829bf01..1fda5c7c2cfc 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -86,6 +86,9 @@ struct geni_i2c_dev { u32 clk_freq_out; const struct geni_i2c_clk_fld *clk_fld; int suspended;
dma_addr_t tx_dma;
dma_addr_t rx_dma;
size_t xfer_len; };
struct geni_i2c_err_log {
@@ -358,6 +361,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, struct geni_se *se = &gi2c->se; size_t len = msg->len;
- gi2c->xfer_len = msg->len;
nit: gi2c->xfer = len, for tx_one_msg as well.
Regards,
Akash
if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
@@ -384,6 +388,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_rx_fsm_rst(gi2c);
gi2c->rx_dma = rx_dma;@@ -400,6 +405,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, struct geni_se *se = &gi2c->se; size_t len = msg->len;
- gi2c->xfer_len = msg->len; if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
@@ -429,6 +435,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_tx_fsm_rst(gi2c);
gi2c->tx_dma = tx_dma;
On 2020-08-26 17:25, Akash Asthana wrote:
Hi Roja,
On 8/20/2020 4:05 PM, Roja Rani Yarubandi wrote:
Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping data scope. For example during shutdown callback to unmap DMA mapping, this stored DMA mapping data can be used to call geni_se_tx_dma_unprep and geni_se_rx_dma_unprep functions.
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
Changes in V2:
- As per Stephen's comments, changed commit text, fixed minor
nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 7f130829bf01..1fda5c7c2cfc 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -86,6 +86,9 @@ struct geni_i2c_dev { u32 clk_freq_out; const struct geni_i2c_clk_fld *clk_fld; int suspended;
- dma_addr_t tx_dma;
- dma_addr_t rx_dma;
- size_t xfer_len; }; struct geni_i2c_err_log {
@@ -358,6 +361,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, struct geni_se *se = &gi2c->se; size_t len = msg->len;
- gi2c->xfer_len = msg->len;
nit: gi2c->xfer = len, for tx_one_msg as well.
Regards,
Akash
Okay
if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); @@ -384,6 +388,7 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_rx_fsm_rst(gi2c);
gi2c->rx_dma = rx_dma;@@ -400,6 +405,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, struct geni_se *se = &gi2c->se; size_t len = msg->len;
- gi2c->xfer_len = msg->len;
if (!of_machine_is_compatible("lenovo,yoga-c630")) dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); @@ -429,6 +435,7 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, if (dma_buf) { if (gi2c->err) geni_i2c_tx_fsm_rst(gi2c);
gi2c->tx_dma = tx_dma;
If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors.
So, implement shutdown callback to i2c driver to unmap DMA mappings during system "reboot" or "shutdown".
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org --- Changes in V2: - As per Stephen's comments added seperate function for stop transfer, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 43 ++++++++++++++++++++++++++++++ include/linux/qcom-geni-se.h | 5 ++++ 2 files changed, 48 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 1fda5c7c2cfc..d07f2f33bb75 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -486,6 +486,28 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, return ret; }
+static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{ + u32 val; + struct geni_se *se = &gi2c->se; + + val = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0); + if (val & DMA_TX_ACTIVE) { + geni_i2c_abort_xfer(gi2c); + gi2c->cur_wr = 0; + if (gi2c->err) + geni_i2c_tx_fsm_rst(gi2c); + geni_se_tx_dma_unprep(se, gi2c->tx_dma, gi2c->xfer_len); + } + if (val & DMA_RX_ACTIVE) { + geni_i2c_abort_xfer(gi2c); + gi2c->cur_rd = 0; + if (gi2c->err) + geni_i2c_rx_fsm_rst(gi2c); + geni_se_rx_dma_unprep(se, gi2c->rx_dma, gi2c->xfer_len); + } +} + static u32 geni_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); @@ -617,6 +639,26 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; }
+static void geni_i2c_shutdown(struct platform_device *pdev) +{ + int ret; + u32 dma; + struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev); + struct geni_se *se = &gi2c->se; + + ret = pm_runtime_get_sync(gi2c->se.dev); + if (ret < 0) { + dev_err(gi2c->se.dev, "Failed to resume device: %d\n", ret); + return; + } + + dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN); + if (dma) + geni_i2c_stop_xfer(gi2c); + + pm_runtime_put_sync_suspend(gi2c->se.dev); +} + static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) { int ret; @@ -677,6 +719,7 @@ MODULE_DEVICE_TABLE(of, geni_i2c_dt_match); static struct platform_driver geni_i2c_driver = { .probe = geni_i2c_probe, .remove = geni_i2c_remove, + .shutdown = geni_i2c_shutdown, .driver = { .name = "geni_i2c", .pm = &geni_i2c_pm_ops, diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h index dd464943f717..c3c016496d98 100644 --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -77,6 +77,7 @@ struct geni_se { #define SE_DMA_RX_FSM_RST 0xd58 #define SE_HW_PARAM_0 0xe24 #define SE_HW_PARAM_1 0xe28 +#define SE_DMA_DEBUG_REG0 0xe40
/* GENI_FORCE_DEFAULT_REG fields */ #define FORCE_DEFAULT BIT(0) @@ -207,6 +208,10 @@ struct geni_se { #define RX_GENI_CANCEL_IRQ BIT(11) #define RX_GENI_GP_IRQ_EXT GENMASK(13, 12)
+/* SE_DMA_DEBUG_REG0 Register fields */ +#define DMA_TX_ACTIVE BIT(0) +#define DMA_RX_ACTIVE BIT(1) + /* SE_HW_PARAM_0 fields */ #define TX_FIFO_WIDTH_MSK GENMASK(29, 24) #define TX_FIFO_WIDTH_SHFT 24
Quoting Roja Rani Yarubandi (2020-08-20 03:35:22)
If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors.
So, implement shutdown callback to i2c driver to unmap DMA mappings during system "reboot" or "shutdown".
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
I'd still put a Fixes tag because it's fixing the driver when someone runs shutdown.
Changes in V2:
- As per Stephen's comments added seperate function for stop transfer, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 43 ++++++++++++++++++++++++++++++ include/linux/qcom-geni-se.h | 5 ++++ 2 files changed, 48 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 1fda5c7c2cfc..d07f2f33bb75 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -486,6 +486,28 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, return ret; }
+static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{
u32 val;struct geni_se *se = &gi2c->se;val = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0);if (val & DMA_TX_ACTIVE) {geni_i2c_abort_xfer(gi2c);gi2c->cur_wr = 0;if (gi2c->err)geni_i2c_tx_fsm_rst(gi2c);geni_se_tx_dma_unprep(se, gi2c->tx_dma, gi2c->xfer_len);}if (val & DMA_RX_ACTIVE) {geni_i2c_abort_xfer(gi2c);gi2c->cur_rd = 0;if (gi2c->err)geni_i2c_rx_fsm_rst(gi2c);geni_se_rx_dma_unprep(se, gi2c->rx_dma, gi2c->xfer_len);}+}
static u32 geni_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); @@ -617,6 +639,26 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; }
+static void geni_i2c_shutdown(struct platform_device *pdev) +{
int ret;u32 dma;struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);struct geni_se *se = &gi2c->se;ret = pm_runtime_get_sync(gi2c->se.dev);if (ret < 0) {dev_err(gi2c->se.dev, "Failed to resume device: %d\n", ret);return;}dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);if (dma)geni_i2c_stop_xfer(gi2c);
Any reason the if (dma) check isn't inside geni_i2c_stop_xfer()? Checking for dma and then bailing out early should work and keep the logic in one function. Then the pm_runtime_sync() call could go in there too and if (!dma) goto out. This assumes that we're going to call geni_i2c_stop_xfer() from somewhere else, like if a transfer times out or something?
pm_runtime_put_sync_suspend(gi2c->se.dev);+}
static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) { int ret;
On 2020-08-21 05:52, Stephen Boyd wrote:
Quoting Roja Rani Yarubandi (2020-08-20 03:35:22)
If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors.
So, implement shutdown callback to i2c driver to unmap DMA mappings during system "reboot" or "shutdown".
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
I'd still put a Fixes tag because it's fixing the driver when someone runs shutdown.
Okay, will add fixes tag.
Changes in V2:
- As per Stephen's comments added seperate function for stop
transfer, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 43 ++++++++++++++++++++++++++++++ include/linux/qcom-geni-se.h | 5 ++++ 2 files changed, 48 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 1fda5c7c2cfc..d07f2f33bb75 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -486,6 +486,28 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, return ret; }
+static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{
u32 val;struct geni_se *se = &gi2c->se;val = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0);if (val & DMA_TX_ACTIVE) {geni_i2c_abort_xfer(gi2c);gi2c->cur_wr = 0;if (gi2c->err)geni_i2c_tx_fsm_rst(gi2c);geni_se_tx_dma_unprep(se, gi2c->tx_dma,gi2c->xfer_len);
}if (val & DMA_RX_ACTIVE) {geni_i2c_abort_xfer(gi2c);gi2c->cur_rd = 0;if (gi2c->err)geni_i2c_rx_fsm_rst(gi2c);geni_se_rx_dma_unprep(se, gi2c->rx_dma,gi2c->xfer_len);
}+}
static u32 geni_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); @@ -617,6 +639,26 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; }
+static void geni_i2c_shutdown(struct platform_device *pdev) +{
int ret;u32 dma;struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);struct geni_se *se = &gi2c->se;ret = pm_runtime_get_sync(gi2c->se.dev);if (ret < 0) {dev_err(gi2c->se.dev, "Failed to resume device: %d\n",ret);
return;}dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);if (dma)geni_i2c_stop_xfer(gi2c);Any reason the if (dma) check isn't inside geni_i2c_stop_xfer()? Checking for dma and then bailing out early should work and keep the logic in one function. Then the pm_runtime_sync() call could go in there too and if (!dma) goto out. This assumes that we're going to call geni_i2c_stop_xfer() from somewhere else, like if a transfer times out or something?
Okay, will do the changes.
pm_runtime_put_sync_suspend(gi2c->se.dev);+}
static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) { int ret;
Hi Roja,
On 8/20/2020 4:05 PM, Roja Rani Yarubandi wrote:
If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors.
So, implement shutdown callback to i2c driver to unmap DMA mappings during system "reboot" or "shutdown".
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
Changes in V2:
- As per Stephen's comments added seperate function for stop transfer, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 43 ++++++++++++++++++++++++++++++ include/linux/qcom-geni-se.h | 5 ++++ 2 files changed, 48 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 1fda5c7c2cfc..d07f2f33bb75 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -486,6 +486,28 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, return ret; }
+static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{
- u32 val;
- struct geni_se *se = &gi2c->se;
- val = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0);
- if (val & DMA_TX_ACTIVE) {
geni_i2c_abort_xfer(gi2c);gi2c->cur_wr = 0;if (gi2c->err)geni_i2c_tx_fsm_rst(gi2c);geni_se_tx_dma_unprep(se, gi2c->tx_dma, gi2c->xfer_len);- }
should be 'else if', because TX and RX can't happen parallel.
- if (val & DMA_RX_ACTIVE) {
geni_i2c_abort_xfer(gi2c);gi2c->cur_rd = 0;if (gi2c->err)geni_i2c_rx_fsm_rst(gi2c);geni_se_rx_dma_unprep(se, gi2c->rx_dma, gi2c->xfer_len);- }
+}
- static u32 geni_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
@@ -617,6 +639,26 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; }
+static void geni_i2c_shutdown(struct platform_device *pdev) +{
- int ret;
- u32 dma;
- struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
- struct geni_se *se = &gi2c->se;
- ret = pm_runtime_get_sync(gi2c->se.dev);
- if (ret < 0) {
dev_err(gi2c->se.dev, "Failed to resume device: %d\n", ret);return;- }
- dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
Wrt to current issue context it may be suffice to stop just DMA mode transfers but why not stop all mode of active transfer during shutdown in a generic way.
Regards,
Akash
- if (dma)
geni_i2c_stop_xfer(gi2c);- pm_runtime_put_sync_suspend(gi2c->se.dev);
+}
- static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) { int ret;
@@ -677,6 +719,7 @@ MODULE_DEVICE_TABLE(of, geni_i2c_dt_match); static struct platform_driver geni_i2c_driver = { .probe = geni_i2c_probe, .remove = geni_i2c_remove,
- .shutdown = geni_i2c_shutdown, .driver = { .name = "geni_i2c", .pm = &geni_i2c_pm_ops,
diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h index dd464943f717..c3c016496d98 100644 --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -77,6 +77,7 @@ struct geni_se { #define SE_DMA_RX_FSM_RST 0xd58 #define SE_HW_PARAM_0 0xe24 #define SE_HW_PARAM_1 0xe28 +#define SE_DMA_DEBUG_REG0 0xe40
/* GENI_FORCE_DEFAULT_REG fields */ #define FORCE_DEFAULT BIT(0) @@ -207,6 +208,10 @@ struct geni_se { #define RX_GENI_CANCEL_IRQ BIT(11) #define RX_GENI_GP_IRQ_EXT GENMASK(13, 12)
+/* SE_DMA_DEBUG_REG0 Register fields */ +#define DMA_TX_ACTIVE BIT(0) +#define DMA_RX_ACTIVE BIT(1)
- /* SE_HW_PARAM_0 fields */ #define TX_FIFO_WIDTH_MSK GENMASK(29, 24) #define TX_FIFO_WIDTH_SHFT 24
On 2020-08-26 17:26, Akash Asthana wrote:
Hi Roja,
On 8/20/2020 4:05 PM, Roja Rani Yarubandi wrote:
If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors.
So, implement shutdown callback to i2c driver to unmap DMA mappings during system "reboot" or "shutdown".
Signed-off-by: Roja Rani Yarubandi rojay@codeaurora.org
Changes in V2:
- As per Stephen's comments added seperate function for stop
transfer, fixed minor nitpicks.
drivers/i2c/busses/i2c-qcom-geni.c | 43 ++++++++++++++++++++++++++++++ include/linux/qcom-geni-se.h | 5 ++++ 2 files changed, 48 insertions(+)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index 1fda5c7c2cfc..d07f2f33bb75 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -486,6 +486,28 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, return ret; } +static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{
- u32 val;
- struct geni_se *se = &gi2c->se;
- val = readl_relaxed(gi2c->se.base + SE_DMA_DEBUG_REG0);
- if (val & DMA_TX_ACTIVE) {
geni_i2c_abort_xfer(gi2c);gi2c->cur_wr = 0;if (gi2c->err)geni_i2c_tx_fsm_rst(gi2c);geni_se_tx_dma_unprep(se, gi2c->tx_dma, gi2c->xfer_len);- }
should be 'else if', because TX and RX can't happen parallel.
- if (val & DMA_RX_ACTIVE) {
geni_i2c_abort_xfer(gi2c);gi2c->cur_rd = 0;if (gi2c->err)geni_i2c_rx_fsm_rst(gi2c);geni_se_rx_dma_unprep(se, gi2c->rx_dma, gi2c->xfer_len);- }
+}
- static u32 geni_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL &
~I2C_FUNC_SMBUS_QUICK); @@ -617,6 +639,26 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; } +static void geni_i2c_shutdown(struct platform_device *pdev) +{
- int ret;
- u32 dma;
- struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
- struct geni_se *se = &gi2c->se;
- ret = pm_runtime_get_sync(gi2c->se.dev);
- if (ret < 0) {
dev_err(gi2c->se.dev, "Failed to resume device: %d\n", ret);return;- }
- dma = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
Wrt to current issue context it may be suffice to stop just DMA mode transfers but why not stop all mode of active transfer during shutdown in a generic way.
Regards,
Akash
Okay, I will include FIFO transfer case also in stop_xfer
- if (dma)
geni_i2c_stop_xfer(gi2c);- pm_runtime_put_sync_suspend(gi2c->se.dev);
+}
- static int __maybe_unused geni_i2c_runtime_suspend(struct device
*dev) { int ret; @@ -677,6 +719,7 @@ MODULE_DEVICE_TABLE(of, geni_i2c_dt_match); static struct platform_driver geni_i2c_driver = { .probe = geni_i2c_probe, .remove = geni_i2c_remove,
- .shutdown = geni_i2c_shutdown, .driver = { .name = "geni_i2c", .pm = &geni_i2c_pm_ops,
diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h index dd464943f717..c3c016496d98 100644 --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -77,6 +77,7 @@ struct geni_se { #define SE_DMA_RX_FSM_RST 0xd58 #define SE_HW_PARAM_0 0xe24 #define SE_HW_PARAM_1 0xe28 +#define SE_DMA_DEBUG_REG0 0xe40 /* GENI_FORCE_DEFAULT_REG fields */ #define FORCE_DEFAULT BIT(0) @@ -207,6 +208,10 @@ struct geni_se { #define RX_GENI_CANCEL_IRQ BIT(11) #define RX_GENI_GP_IRQ_EXT GENMASK(13, 12) +/* SE_DMA_DEBUG_REG0 Register fields */ +#define DMA_TX_ACTIVE BIT(0) +#define DMA_RX_ACTIVE BIT(1)
- /* SE_HW_PARAM_0 fields */ #define TX_FIFO_WIDTH_MSK GENMASK(29, 24) #define TX_FIFO_WIDTH_SHFT 24
dri-devel@lists.freedesktop.org
-
Akash Asthana -
Roja Rani Yarubandi -
rojay＠codeaurora.org
-
Stephen Boyd