Re: [PATCH v3 3/9] remoteproc: qcom_q6v5_mss: Add MDM9607

[Bryan O'Donoghue]

On 01/01/2026 13:13, Bryan O'Donoghue wrote:
On 31/12/2025 16:30, Barnabás Czémán wrote:
From: Stephan Gerhold <step...@gerhold.net>
Add support for MDM9607 MSS it have different ACC settings
and it needs mitigation for inrush current issue.

Signed-off-by: Stephan Gerhold <step...@gerhold.net>
[Reword the commit, add necessary flags, rework inrush current mitigation]
Signed-off-by: Barnabás Czémán <barnabas.cze...@mainlining.org>
---
   drivers/remoteproc/qcom_q6v5_mss.c | 89 
++++++++++++++++++++++++++++++++------
   1 file changed, 75 insertions(+), 14 deletions(-)

diff --git a/drivers/remoteproc/qcom_q6v5_mss.c 
b/drivers/remoteproc/qcom_q6v5_mss.c
index 3c404118b322..19863c576d72 100644
--- a/drivers/remoteproc/qcom_q6v5_mss.c
+++ b/drivers/remoteproc/qcom_q6v5_mss.c
@@ -124,6 +124,7 @@
   #define QDSP6v56_CLAMP_QMC_MEM               BIT(22)
   #define QDSP6SS_XO_CBCR              0x0038
   #define QDSP6SS_ACC_OVERRIDE_VAL             0x20
+#define QDSP6SS_ACC_OVERRIDE_VAL_9607  0x80800000
   #define QDSP6v55_BHS_EN_REST_ACK     BIT(0)

   /* QDSP6v65 parameters */
@@ -256,6 +257,7 @@ struct q6v5 {
   };

   enum {
+       MSS_MDM9607,
        MSS_MSM8226,
        MSS_MSM8909,
        MSS_MSM8916,
@@ -747,15 +749,19 @@ static int q6v5proc_reset(struct q6v5 *qproc)
                        return ret;
                }
                goto pbl_wait;
-       } else if (qproc->version == MSS_MSM8909 ||
+       } else if (qproc->version == MSS_MDM9607 ||
+                  qproc->version == MSS_MSM8909 ||
                   qproc->version == MSS_MSM8953 ||
                   qproc->version == MSS_MSM8996 ||
                   qproc->version == MSS_MSM8998 ||
                   qproc->version == MSS_SDM660) {

-               if (qproc->version != MSS_MSM8909 &&
-                   qproc->version != MSS_MSM8953)
-                       /* Override the ACC value if required */
+               /* Override the ACC value if required */
+               if (qproc->version == MSS_MDM9607)
+                       writel(QDSP6SS_ACC_OVERRIDE_VAL_9607,
+                              qproc->reg_base + QDSP6SS_STRAP_ACC);
+               else if (qproc->version != MSS_MSM8909 &&
+                        qproc->version != MSS_MSM8953)
                        writel(QDSP6SS_ACC_OVERRIDE_VAL,
                               qproc->reg_base + QDSP6SS_STRAP_ACC);

@@ -800,7 +806,7 @@ static int q6v5proc_reset(struct q6v5 *qproc)
                writel(val, qproc->reg_base + QDSP6SS_PWR_CTL_REG);

                if (qproc->version != MSS_MSM8909) {
-                       int mem_pwr_ctl;
+                       int mem_pwr_ctl, reverse = 0;

                        /* Deassert QDSP6 compiler memory clamp */
                        val = readl(qproc->reg_base + QDSP6SS_PWR_CTL_REG);
@@ -812,7 +818,8 @@ static int q6v5proc_reset(struct q6v5 *qproc)
                        writel(val, qproc->reg_base + QDSP6SS_PWR_CTL_REG);

                        /* Turn on L1, L2, ETB and JU memories 1 at a time */
-                       if (qproc->version == MSS_MSM8953 ||
+                       if (qproc->version == MSS_MDM9607 ||
+                           qproc->version == MSS_MSM8953 ||
                            qproc->version == MSS_MSM8996) {
                                mem_pwr_ctl = QDSP6SS_MEM_PWR_CTL;
                                i = 19;
@@ -822,16 +829,34 @@ static int q6v5proc_reset(struct q6v5 *qproc)
                                i = 28;
                        }
                        val = readl(qproc->reg_base + mem_pwr_ctl);
-                       for (; i >= 0; i--) {
-                               val |= BIT(i);
-                               writel(val, qproc->reg_base + mem_pwr_ctl);
+                       if (qproc->version == MSS_MDM9607) {
                                /*
-                                * Read back value to ensure the write is done 
then
-                                * wait for 1us for both memory peripheral and 
data
-                                * array to turn on.
+                                * Set first 5 bits in reverse to avoid
+                                * "inrush current" issues.
                                 */
-                               val |= readl(qproc->reg_base + mem_pwr_ctl);
-                               udelay(1);
+                               reverse = 6;
+                               for (; i >= reverse; i--) {
+                                       val |= BIT(i);
+                                       writel(val, qproc->reg_base + 
mem_pwr_ctl);
+                                       udelay(1);
+                               }
+                               for (i = 0; i < reverse; i++) {
+                                       val |= BIT(i);
+                                       writel(val, qproc->reg_base + 
mem_pwr_ctl);
+                                       udelay(1);
+                               }
+                       } else {
+                               for (; i >= 0; i--) {
+                                       val |= BIT(i);
+                                       writel(val, qproc->reg_base + 
mem_pwr_ctl);
+                                       /*
+                                        * Read back value to ensure the write 
is done then
+                                        * wait for 1us for both memory 
peripheral and data
+                                        * array to turn on.
+                                        */
+                                       val |= readl(qproc->reg_base + 
mem_pwr_ctl);
+                                       udelay(1);

Isn't the logic here inverted ?

i.e. you've written a thing and ostensibly require a delay for that
thing to take effect, the power to switch on in this case.

It makes more sense to write, delay and read back rather than write,
readback and delay surely...

Also now that I look at this, shouldn't you interrogate the bit gets set 
as per your write ?

Does this bit mean "yes I acknowledge your request" or "yes I carried 
out your request" ?

In the first case you care that the bit indicates something useful, in 
the second case it barely indicates anything at all.

---
bod