* [PATCH v2] i2c: bcm-iproc: Add i2c recovery support
@ 2021-06-01 23:07 Chris Packham
2021-06-02 2:11 ` kernel test robot
0 siblings, 1 reply; 2+ messages in thread
From: Chris Packham @ 2021-06-01 23:07 UTC (permalink / raw)
To: wsa, rjui, sbranden, bcm-kernel-feedback-list
Cc: linux-i2c, linux-arm-kernel, linux-kernel, Richard Laing, Chris Packham
From: Richard Laing <richard.laing@alliedtelesis.co.nz>
The bcm-iproc controller can put the SDA/SCL lines into bit-bang mode,
make use of this to support i2c bus recovery.
Signed-off-by: Richard Laing <richard.laing@alliedtelesis.co.nz>
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
Richard did most of the work on this. I'm just cleaning it up to get it
upstream.
Changes in v2:
- Incorporate feedback from Ray Jui
- Move bcm_iproc_i2c_resume so it can be re-used to return the i2c bus
to normal operation at the correct speed after a recovery.
- Add iproc_i2c_lockup_recover() helper to only trigger recovery if sda
is actually stuck
- Use usleep_range() instead of udelay()
- Cosmetic changes to register bit definitions
drivers/i2c/busses/i2c-bcm-iproc.c | 176 +++++++++++++++++++++++++----
1 file changed, 151 insertions(+), 25 deletions(-)
diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c
index cceaf69279a9..417eb8d69d54 100644
--- a/drivers/i2c/busses/i2c-bcm-iproc.c
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -25,6 +25,7 @@
#define CFG_OFFSET 0x00
#define CFG_RESET_SHIFT 31
#define CFG_EN_SHIFT 30
+#define CFG_BIT_BANG_SHIFT 29
#define CFG_SLAVE_ADDR_0_SHIFT 28
#define CFG_M_RETRY_CNT_SHIFT 16
#define CFG_M_RETRY_CNT_MASK 0x0f
@@ -66,6 +67,12 @@
#define S_FIFO_RX_THLD_SHIFT 8
#define S_FIFO_RX_THLD_MASK 0x3f
+#define M_BB_CTRL_OFFSET 0x14
+#define M_BB_SMBCLK_IN_SHIFT 31
+#define M_BB_SMBCLK_OUT_EN_SHIFT 30
+#define M_BB_SMBDAT_IN_SHIFT 29
+#define M_BB_SMBDAT_OUT_EN_SHIFT 28
+
#define M_CMD_OFFSET 0x30
#define M_CMD_START_BUSY_SHIFT 31
#define M_CMD_STATUS_SHIFT 25
@@ -713,6 +720,147 @@ static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
}
+static int bcm_iproc_i2c_resume(struct device *dev)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
+ int ret;
+ u32 val;
+
+ /*
+ * Power domain could have been shut off completely in system deep
+ * sleep, so re-initialize the block here
+ */
+ ret = bcm_iproc_i2c_init(iproc_i2c);
+ if (ret)
+ return ret;
+
+ /* configure to the desired bus speed */
+ val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
+ val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
+ val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
+ iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
+
+ bcm_iproc_i2c_enable_disable(iproc_i2c, true);
+
+ return 0;
+}
+
+static void bcm_iproc_i2c_prepare_recovery(struct i2c_adapter *adap)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+ u32 tmp;
+
+ dev_dbg(iproc_i2c->device, "Prepare recovery\n");
+
+ /* Disable interrupts */
+ writel(0, iproc_i2c->base + IE_OFFSET);
+ readl(iproc_i2c->base + IE_OFFSET);
+ synchronize_irq(iproc_i2c->irq);
+
+ /* Place controller in reset */
+ tmp = readl(iproc_i2c->base + CFG_OFFSET);
+ tmp |= BIT(CFG_RESET_SHIFT);
+ writel(tmp, iproc_i2c->base + CFG_OFFSET);
+ usleep_range(100, 200);
+
+ /* Switch to bit-bang mode */
+ tmp = readl(iproc_i2c->base + CFG_OFFSET);
+ tmp |= BIT(CFG_BIT_BANG_SHIFT);
+ writel(tmp, iproc_i2c->base + CFG_OFFSET);
+ usleep_range(100, 200);
+}
+
+static void bcm_iproc_i2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+ u32 tmp;
+
+ /* Switch to normal mode */
+ tmp = readl(iproc_i2c->base + CFG_OFFSET);
+ tmp &= ~BIT(CFG_BIT_BANG_SHIFT);
+ writel(tmp, iproc_i2c->base + CFG_OFFSET);
+ usleep_range(100, 200);
+
+ bcm_iproc_i2c_resume(iproc_i2c->device);
+
+ dev_dbg(iproc_i2c->device, "Recovery complete\n");
+}
+
+static int bcm_iproc_i2c_get_scl(struct i2c_adapter *adap)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+ u32 tmp;
+
+ tmp = readl(iproc_i2c->base + M_BB_CTRL_OFFSET);
+
+ return !!(tmp & BIT(M_BB_SMBCLK_IN_SHIFT));
+}
+
+static void bcm_iproc_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+ u32 tmp;
+
+ tmp = readl(iproc_i2c->base + M_BB_CTRL_OFFSET);
+ if (val)
+ tmp |= BIT(M_BB_SMBCLK_OUT_EN_SHIFT);
+ else
+ tmp &= ~BIT(M_BB_SMBCLK_OUT_EN_SHIFT);
+
+ writel(tmp, iproc_i2c->base + M_BB_CTRL_OFFSET);
+}
+
+static void bcm_iproc_i2c_set_sda(struct i2c_adapter *adap, int val)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+ u32 tmp;
+
+ tmp = readl(iproc_i2c->base + M_BB_CTRL_OFFSET);
+ if (val)
+ tmp |= BIT(M_BB_SMBDAT_OUT_EN_SHIFT);
+ else
+ tmp &= ~BIT(M_BB_SMBDAT_OUT_EN_SHIFT);
+
+ writel(tmp, iproc_i2c->base + M_BB_CTRL_OFFSET);
+}
+
+static int bcm_iproc_i2c_get_sda(struct i2c_adapter *adap)
+{
+ struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adap);
+ u32 tmp;
+
+ tmp = readl(iproc_i2c->base + M_BB_CTRL_OFFSET);
+
+ return !!(tmp & BIT(M_BB_SMBDAT_IN_SHIFT));
+}
+
+/* Check if bus lockup occurred, and invoke recovery if so. */
+static void iproc_i2c_lockup_recover(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+ /*
+ * assume bus lockup if SDA line is low;
+ * note that there is no need to switch to
+ * bit-bang mode for this check.
+ */
+ if (!bcm_iproc_i2c_get_sda(&iproc_i2c->adapter)) {
+ /* locked up - invoke i2c bus recovery. */
+ int ret = i2c_recover_bus(&iproc_i2c->adapter);
+
+ if (ret)
+ dev_err(iproc_i2c->device, "bus recovery: error %d\n", ret);
+ }
+}
+
+static const struct i2c_bus_recovery_info bcm_iproc_recovery_info = {
+ .recover_bus = i2c_generic_scl_recovery,
+ .prepare_recovery = bcm_iproc_i2c_prepare_recovery,
+ .unprepare_recovery = bcm_iproc_i2c_unprepare_recovery,
+ .set_scl = bcm_iproc_i2c_set_scl,
+ .get_scl = bcm_iproc_i2c_get_scl,
+ .set_sda = bcm_iproc_i2c_set_sda,
+ .get_sda = bcm_iproc_i2c_get_sda,
+};
+
static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c,
struct i2c_msg *msg)
{
@@ -806,6 +954,7 @@ static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
/* flush both TX/RX FIFOs */
val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
+ iproc_i2c_lockup_recover(iproc_i2c);
return -ETIMEDOUT;
}
@@ -814,6 +963,7 @@ static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
/* flush both TX/RX FIFOs */
val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
+ iproc_i2c_lockup_recover(iproc_i2c);
return ret;
}
@@ -1111,6 +1261,7 @@ static int bcm_iproc_i2c_probe(struct platform_device *pdev)
of_node_full_name(iproc_i2c->device->of_node));
adap->algo = &bcm_iproc_algo;
adap->quirks = &bcm_iproc_i2c_quirks;
+ adap->bus_recovery_info = &bcm_iproc_recovery_info;
adap->dev.parent = &pdev->dev;
adap->dev.of_node = pdev->dev.of_node;
@@ -1159,31 +1310,6 @@ static int bcm_iproc_i2c_suspend(struct device *dev)
return 0;
}
-static int bcm_iproc_i2c_resume(struct device *dev)
-{
- struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
- int ret;
- u32 val;
-
- /*
- * Power domain could have been shut off completely in system deep
- * sleep, so re-initialize the block here
- */
- ret = bcm_iproc_i2c_init(iproc_i2c);
- if (ret)
- return ret;
-
- /* configure to the desired bus speed */
- val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
- val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
- val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
- iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
-
- bcm_iproc_i2c_enable_disable(iproc_i2c, true);
-
- return 0;
-}
-
static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = {
.suspend_late = &bcm_iproc_i2c_suspend,
.resume_early = &bcm_iproc_i2c_resume
--
2.31.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH v2] i2c: bcm-iproc: Add i2c recovery support
2021-06-01 23:07 [PATCH v2] i2c: bcm-iproc: Add i2c recovery support Chris Packham
@ 2021-06-02 2:11 ` kernel test robot
0 siblings, 0 replies; 2+ messages in thread
From: kernel test robot @ 2021-06-02 2:11 UTC (permalink / raw)
To: Chris Packham, wsa, rjui, sbranden, bcm-kernel-feedback-list
Cc: kbuild-all, clang-built-linux, linux-i2c, linux-arm-kernel,
linux-kernel, Richard Laing, Chris Packham
[-- Attachment #1: Type: text/plain, Size: 5399 bytes --]
Hi Chris,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on wsa/i2c/for-next]
[also build test ERROR on v5.13-rc4 next-20210601]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Chris-Packham/i2c-bcm-iproc-Add-i2c-recovery-support/20210602-070900
base: https://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/for-next
config: arm64-randconfig-r003-20210601 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project db26cd30b6dd65e88d786e97a1e453af5cd48966)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm64 cross compiling tool for clang build
# apt-get install binutils-aarch64-linux-gnu
# https://github.com/0day-ci/linux/commit/9671d44b08834b225120a1288271bb38c01c1f33
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Chris-Packham/i2c-bcm-iproc-Add-i2c-recovery-support/20210602-070900
git checkout 9671d44b08834b225120a1288271bb38c01c1f33
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
drivers/i2c/busses/i2c-bcm-iproc.c:1199:3: warning: cast to smaller integer type 'enum bcm_iproc_i2c_type' from 'const void *' [-Wvoid-pointer-to-enum-cast]
(enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/i2c/busses/i2c-bcm-iproc.c:1264:26: error: assigning to 'struct i2c_bus_recovery_info *' from 'const struct i2c_bus_recovery_info *' discards qualifiers [-Werror,-Wincompatible-pointer-types-discards-qualifiers]
adap->bus_recovery_info = &bcm_iproc_recovery_info;
^ ~~~~~~~~~~~~~~~~~~~~~~~~
1 warning and 1 error generated.
vim +1264 drivers/i2c/busses/i2c-bcm-iproc.c
1183
1184 static int bcm_iproc_i2c_probe(struct platform_device *pdev)
1185 {
1186 int irq, ret = 0;
1187 struct bcm_iproc_i2c_dev *iproc_i2c;
1188 struct i2c_adapter *adap;
1189 struct resource *res;
1190
1191 iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c),
1192 GFP_KERNEL);
1193 if (!iproc_i2c)
1194 return -ENOMEM;
1195
1196 platform_set_drvdata(pdev, iproc_i2c);
1197 iproc_i2c->device = &pdev->dev;
1198 iproc_i2c->type =
1199 (enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);
1200 init_completion(&iproc_i2c->done);
1201
1202 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1203 iproc_i2c->base = devm_ioremap_resource(iproc_i2c->device, res);
1204 if (IS_ERR(iproc_i2c->base))
1205 return PTR_ERR(iproc_i2c->base);
1206
1207 if (iproc_i2c->type == IPROC_I2C_NIC) {
1208 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1209 iproc_i2c->idm_base = devm_ioremap_resource(iproc_i2c->device,
1210 res);
1211 if (IS_ERR(iproc_i2c->idm_base))
1212 return PTR_ERR(iproc_i2c->idm_base);
1213
1214 ret = of_property_read_u32(iproc_i2c->device->of_node,
1215 "brcm,ape-hsls-addr-mask",
1216 &iproc_i2c->ape_addr_mask);
1217 if (ret < 0) {
1218 dev_err(iproc_i2c->device,
1219 "'brcm,ape-hsls-addr-mask' missing\n");
1220 return -EINVAL;
1221 }
1222
1223 spin_lock_init(&iproc_i2c->idm_lock);
1224
1225 /* no slave support */
1226 bcm_iproc_algo.reg_slave = NULL;
1227 bcm_iproc_algo.unreg_slave = NULL;
1228 }
1229
1230 ret = bcm_iproc_i2c_init(iproc_i2c);
1231 if (ret)
1232 return ret;
1233
1234 ret = bcm_iproc_i2c_cfg_speed(iproc_i2c);
1235 if (ret)
1236 return ret;
1237
1238 irq = platform_get_irq(pdev, 0);
1239 if (irq > 0) {
1240 ret = devm_request_irq(iproc_i2c->device, irq,
1241 bcm_iproc_i2c_isr, 0, pdev->name,
1242 iproc_i2c);
1243 if (ret < 0) {
1244 dev_err(iproc_i2c->device,
1245 "unable to request irq %i\n", irq);
1246 return ret;
1247 }
1248
1249 iproc_i2c->irq = irq;
1250 } else {
1251 dev_warn(iproc_i2c->device,
1252 "no irq resource, falling back to poll mode\n");
1253 }
1254
1255 bcm_iproc_i2c_enable_disable(iproc_i2c, true);
1256
1257 adap = &iproc_i2c->adapter;
1258 i2c_set_adapdata(adap, iproc_i2c);
1259 snprintf(adap->name, sizeof(adap->name),
1260 "Broadcom iProc (%s)",
1261 of_node_full_name(iproc_i2c->device->of_node));
1262 adap->algo = &bcm_iproc_algo;
1263 adap->quirks = &bcm_iproc_i2c_quirks;
> 1264 adap->bus_recovery_info = &bcm_iproc_recovery_info;
1265 adap->dev.parent = &pdev->dev;
1266 adap->dev.of_node = pdev->dev.of_node;
1267
1268 return i2c_add_adapter(adap);
1269 }
1270
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 35222 bytes --]
^ permalink raw reply [flat|nested] 2+ messages in thread
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2021-06-02 2:11 ` kernel test robot
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