Enable DCC and memory dump driver on QLI2.0#217
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jiegan0107 wants to merge 6 commits intoqualcomm-linux:qcom-6.18.yfrom
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Enable DCC and memory dump driver on QLI2.0#217jiegan0107 wants to merge 6 commits intoqualcomm-linux:qcom-6.18.yfrom
jiegan0107 wants to merge 6 commits intoqualcomm-linux:qcom-6.18.yfrom
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…it(DCC) The DCC is a DMA Engine designed to capture and store data during system crash or software triggers. The DCC operates based on user inputs via the debugfs interface. The user gives addresses as inputs and these addresses are stored in the dcc sram. In case of a system crash or a manual software trigger by the user through the debugfs interface, the dcc captures and stores the values at these addresses. This patch contains the driver which has all the methods pertaining to the debugfs interface, auxiliary functions to support all the four fundamental operations of dcc namely read, write, read/modify/write and loop. The probe method here instantiates all the resources necessary for dcc to operate mainly the dedicated dcc sram where it stores the values. The DCC driver can be used for debugging purposes without going for a reboot since it can perform software triggers as well based on user inputs. Also add the documentation for debugfs entries which explains the functionalities of each debugfs file that has been created for dcc. The following is the justification of using debugfs interface over the other alternatives like sysfs/ioctls i) As can be seen from the debugfs attribute descriptions, some of the debugfs attribute files here contains multiple arguments which needs to be accepted from the user. This goes against the design style of sysfs. ii) The user input patterns have been made simple and convenient in this case with the use of debugfs interface as user doesn't need to shuffle between different files to execute one instruction as was the case on using other alternatives. Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
The config file is created to contain specific debug features such as DCC/memory dump driver. Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
Create qcom-dcc dev driver for matching the qcom-dcc driver without DT. Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
The memory dump driver allows various client subsystems to register respective dump regions. At the time of deadlocks or cpu hangs these dump regions are captured to give a snapshot of the system at the time of the crash. Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
Create memory dump device driver for matching the memory dump v2 driver without DT configuration. Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
Memory dump driver needs a large CMA memory zone for storing memory dump table. Add codes for reserving CMA memory during the init stage. Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
Komal-Bajaj
reviewed
Feb 3, 2026
| @@ -0,0 +1 @@ | |||
| CONFIG_QCOM_DCC=m | |||
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can we add these debug configs into kernel/configs/debug.config?
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as these are overlay drivers, Shiraz has suggested to have separate debug config file for containing the configs.
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Further what Amit was suggesting that these configs shouldn’t be enabled in the default build.
So this branch can carry a arch/arm64/configs/qcom_debug.config fragment that optionally enables these debug features.
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DCC and memory dump driver will be enabled on QLI2.0 as overlay drivers (no DT solution)
CRs-Fixed: 4401631