Re: [REBASE PATCH v5 15/17] firmware: scm: Modify only the download bits in TCSR register

[Kathiravan Thirumoorthy]

On 9/11/2023 4:23 PM, Mukesh Ojha wrote:

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: Poovendhan Selvaraj <quic_poove...@quicinc.com>
Signed-off-by: Poovendhan Selvaraj <quic_poove...@quicinc.com>
Signed-off-by: Mukesh Ojha <quic_mo...@quicinc.com>
Tested-by: Kathiravan Thirumoorthy <quic_kathi...@quicinc.com> # IPQ9574 and 
IPQ5332
---
  drivers/firmware/qcom_scm.c | 16 ++++++++++++++--
  1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 321133f0950d..5cacae63ee2a 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -5,6 +5,8 @@
  #include <linux/platform_device.h>
  #include <linux/init.h>
  #include <linux/interrupt.h>
+#include <linux/bitfield.h>
+#include <linux/bits.h>
  #include <linux/completion.h>
  #include <linux/cpumask.h>
  #include <linux/export.h>
@@ -26,6 +28,14 @@
  static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT);
  module_param(download_mode, bool, 0);

+#define SCM_HAS_CORE_CLK BIT(0)

+#define SCM_HAS_IFACE_CLK      BIT(1)
+#define SCM_HAS_BUS_CLK                BIT(2)

Is this intentional to add these macros back again?

+
+#define QCOM_DLOAD_MASK                GENMASK(5, 4)
+#define QCOM_DLOAD_FULLDUMP    0x1
+#define QCOM_DLOAD_NODUMP      0x0
+
  struct qcom_scm {
        struct device *dev;
        struct clk *core_clk;
@@ -440,6 +450,7 @@ static int __qcom_scm_set_dload_mode(struct device *dev, 
bool enable)

static void qcom_scm_set_download_mode(bool enable)

  {
+       u32 val = enable ? QCOM_DLOAD_FULLDUMP : QCOM_DLOAD_NODUMP;
        bool avail;
        int ret = 0;

@@ -449,8 +460,9 @@ static void qcom_scm_set_download_mode(bool enable)

        if (avail) {
                ret = __qcom_scm_set_dload_mode(__scm->dev, 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_update_field(__scm->dload_mode_addr,
+                                              QCOM_DLOAD_MASK,
+                                              FIELD_PREP(QCOM_DLOAD_MASK, 
val));
        } else {
                dev_err(__scm->dev,
                        "No available mechanism for setting download mode\n");