Re: [PATCH V4 5/5] firmware: scm: Modify only the DLOAD bit in TCSR register for download mode
From: Srinivas Kandagatla <hidden>
Date: 2023-02-14 12:57:49
Also in:
linux-arm-msm, linux-clk, linux-devicetree, lkml
On 14/02/2023 05:14, Poovendhan Selvaraj wrote:
quoted hunk ↗ jump to hunk
CrashDump collection is based on the DLOAD bit of TCSR register. To retain other bits, we read the register and modify only the DLOAD bit as the other bits have their own significance. Co-developed-by: Anusha Rao <redacted> Signed-off-by: Anusha Rao <redacted> Co-developed-by: Kathiravan Thirumoorthy <redacted> Signed-off-by: Kathiravan Thirumoorthy <redacted> Signed-off-by: Poovendhan Selvaraj <redacted> --- Changes in V4: - retain the orginal value of tcsr register when download mode is not set drivers/firmware/qcom_scm.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c index 468d4d5ab550..8a34b386ac3a 100644 --- a/drivers/firmware/qcom_scm.c +++ b/drivers/firmware/qcom_scm.c@@ -407,7 +407,7 @@ int qcom_scm_set_remote_state(u32 state, u32 id) } EXPORT_SYMBOL(qcom_scm_set_remote_state); -static int __qcom_scm_set_dload_mode(struct device *dev, bool enable) +static int __qcom_scm_set_dload_mode(struct device *dev, u32 val, bool enable) { struct qcom_scm_desc desc = { .svc = QCOM_SCM_SVC_BOOT,@@ -417,7 +417,8 @@ static int __qcom_scm_set_dload_mode(struct device *dev, bool enable) .owner = ARM_SMCCC_OWNER_SIP, }; - desc.args[1] = enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0; + desc.args[1] = enable ? val | QCOM_SCM_BOOT_SET_DLOAD_MODE : + val & ~(QCOM_SCM_BOOT_SET_DLOAD_MODE);
why not read the value here before setting the DLOAD Mode instead of doing it in qcom_scm_set_download_mode()? that would make the code simple and readable.
quoted hunk ↗ jump to hunk
return qcom_scm_call_atomic(__scm->dev, &desc, NULL); }@@ -426,15 +427,19 @@ static void qcom_scm_set_download_mode(bool enable) { bool avail; int ret = 0; + u32 dload_addr_val; avail = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_SET_DLOAD_MODE); + ret = qcom_scm_io_readl(__scm->dload_mode_addr, &dload_addr_val); +
not checking ret value here before proceeding?
if (avail) {
- ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
+ ret = __qcom_scm_set_dload_mode(__scm->dev, dload_addr_val, enable);
} else if (__scm->dload_mode_addr) {
- ret = qcom_scm_io_writel(__scm->dload_mode_addr,
- enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
+ ret = qcom_scm_io_writel(__scm->dload_mode_addr, enable ?
+ dload_addr_val | QCOM_SCM_BOOT_SET_DLOAD_MODE :
+ dload_addr_val & ~(QCOM_SCM_BOOT_SET_DLOAD_MODE));
} else {
dev_err(__scm->dev,
"No available mechanism for setting download mode\n");_______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel