Re: [PATCH v3 2/3] remoteproc: qcom: Hexagon resource handling

From: Avaneesh Kumar Dwivedi
Date: Mon Nov 21 2016 - 14:29:23 EST

On 11/19/2016 1:00 AM, Bjorn Andersson wrote:
On Wed 16 Nov 07:17 PST 2016, Avaneesh Kumar Dwivedi wrote:

On 11/8/2016 12:19 PM, Bjorn Andersson wrote:
On Mon 07 Nov 04:37 PST 2016, Avaneesh Kumar Dwivedi wrote:

Handling of clock and regulator resources as well as reset
register programing differ according to version of hexagon
dsp hardware. Different version require different resources
and different parameters for same resource. Hence it is
needed that resource handling is generic and independent of
hexagon dsp version.

It would be much easier to review this if you didn't do all three
changes in the same patch, and at the same time changed the function
names. There's large parts of this patch where it's not obvious what the
actual changes are.
OK, have broken patches in very small set of function now.
but patches has increased from 3 to 9.
sorry for inconvenience caused.
I will have a look once we have agreed on below issues.

+ struct regulator **active_regs;
Keeping these as statically sized arrays, potentially with unused
elements at the end removes the need for allocating the storage and the
double pointers.
since i do not know how many resource of a particular type will be needed on
new version of new class of hexagon that is why i am working with pointers.
have removed many entries from above resource struct, it will lok much
cleaner in next patchset.
Just pick the largest number we support right now and then if future
versions need more we increment that number.

struct completion start_done;
struct completion stop_done;
@@ -147,67 +150,245 @@ struct q6v5 {
phys_addr_t mpss_reloc;
void *mpss_region;
size_t mpss_size;
+ struct mutex q6_lock;
+ bool proxy_unvote_reg;
+ bool proxy_unvote_clk;
I still don't see the need for these 3 attributes.
I agree, Have removed them.
-enum {
+static int q6_regulator_init(struct q6v5 *qproc)
+ struct regulator **reg_arr;
+ int i;
+ if (qproc->q6_rproc_res->proxy_reg_cnt) {
If you keep proxy_regs and active_regs as arrays you don't need this
Agree, have removed check.
+ reg_arr = devm_kzalloc(qproc->dev,
+ sizeof(reg_arr) * qproc->q6_rproc_res->proxy_reg_cnt,
+ for (i = 0; i < qproc->q6_rproc_res->proxy_reg_cnt; i++) {
+ reg_arr[i] = devm_regulator_get(qproc->dev,
+ qproc->q6_rproc_res->proxy_regs[i]);
+ if (IS_ERR(reg_arr[i]))
+ return PTR_ERR(reg_arr[i]);
+ qproc->proxy_regs = reg_arr;
+ }
+ }
+ if (qproc->q6_rproc_res->active_reg_cnt) {
+ reg_arr = devm_kzalloc(qproc->dev,
+ sizeof(reg_arr) * qproc->q6_rproc_res->active_reg_cnt,
+ for (i = 0; i < qproc->q6_rproc_res->active_reg_cnt; i++) {
+ reg_arr[i] = devm_regulator_get(qproc->dev,
+ qproc->q6_rproc_res->active_regs[i]);
+ if (IS_ERR(reg_arr[i]))
+ return PTR_ERR(reg_arr[i]);
+ qproc->active_regs = reg_arr;
+ }
+ }
Please keep active_regs and proxy_regs as regulator_bulk_data and
continue to use devm_regulator_bulk_get(), it should make this code
the way i have reorganized code in next patchset i found using
devm_regulator_get() more convenient, can i keep using them? as i am reading
string one by one and based on read string filling a regulator struct with
its voltage and load and handle info.
If it's cleaner, then sure

+ return 0;
-static int q6v5_regulator_init(struct q6v5 *qproc)
+static int q6_proxy_regulator_enable(struct q6v5 *qproc)
- int ret;
+ int i, j, ret = 0;
+ int **reg_loadnvoltsetflag;
+ int *reg_load;
+ int *reg_voltage;
+ reg_loadnvoltsetflag = qproc->q6_rproc_res->proxy_reg_action;
+ reg_load = qproc->q6_rproc_res->proxy_reg_load;
+ reg_voltage = qproc->q6_rproc_res->proxy_reg_voltage;
Rather then keeping these properties on int-arrays I strongly prefer
that you would have a struct { uV, uA } for each regulator.
Have modified as per suggestion.
+ for (i = 0; i < qproc->q6_rproc_res->proxy_reg_cnt; i++) {
+ for (j = 0; j <= 1; j++) {
+ if (j == 0 && *(reg_loadnvoltsetflag + i*j + j))
I'm sorry, but this is not clean. Please use the fact that we're not
writing assembly code and use the language to your advantage.
Sorry for mess, have simplified and cleaned.
+ regulator_set_load(qproc->proxy_regs[i],
+ reg_load[i]);
+ if (j == 1 && *(reg_loadnvoltsetflag + i*j + j))
+ regulator_set_voltage(qproc->proxy_regs[i],
+ reg_voltage[i], INT_MAX);
+ }
+ }
- qproc->supply[Q6V5_SUPPLY_CX].supply = "cx";
- qproc->supply[Q6V5_SUPPLY_MX].supply = "mx";
- qproc->supply[Q6V5_SUPPLY_MSS].supply = "mss";
- qproc->supply[Q6V5_SUPPLY_PLL].supply = "pll";
+ for (i = 0; i < qproc->q6_rproc_res->proxy_reg_cnt; i++) {
+ ret = regulator_enable(qproc->proxy_regs[i]);
+ if (ret) {
+ for (; i > 0; --i) {
+ regulator_disable(qproc->proxy_regs[i]);
+ return ret;
+ }
+ }
+ }
If you just keep your regulators in a regulator_bulk_data array then you
can replace this with regulator_bulk_enable(proxy_reg_cnt, proxy_regs);
As replied above i am going with getting sigle regulator handle one time.
let me know if i can continue or need to change?

The reason for using the bulk operations is that the error path becomes
cleaner, however now that I look at this again; in the event of an error
you leave the regulators with voltage and load specified. You need to
unroll this too.
if regulator enabled failed, i am unrolling the programmed load and voltage setting.
but i will try to incorporate your suggestion.

But I would still prefer that you specify the loads & voltages, then
call bulk_enable() and if that fail remove all load and voltage
OK, will try to incorporate.

- ret = devm_regulator_bulk_get(qproc->dev,
- ARRAY_SIZE(qproc->supply), qproc->supply);
- if (ret < 0) {
- dev_err(qproc->dev, "failed to get supplies\n");
- return ret;
+ if (!strcmp(qproc->q6_rproc_res->q6_version, "v56")) {
This would be much better as an enum than a string. But I keep wonder if
this is only for v5.6 of the Hexagon - perhaps should we clamp different
things on the various versions?.
As replied elsewhere, we need a DT entry to know which version is running,
or else many compatible string will be required. for "v56" there are
following version, so as and when we need to support a new version we will
a new DT entry which when defined will help to take deviation where

Sorry for not seeing this before I answered in the two other places,
perhaps we should just discuss this to end in one place...

But regarding my specific comment, if you want class based handling then

enum {

Then you don't have to use strcmp() to check which class you have.
OK, may i change enum strings as per HPG?

enum {

+ /*
+ * Assert QDSP6 I/O clamp, memory wordline clamp, and compiler
+ * memory clamp as a software workaround to avoid high MX
+ * current during LPASS/MSS restart.
+ */
+ val = readl_relaxed(qproc->reg_base + QDSP6SS_PWR_CTL_REG);
+ val |= (Q6SS_CLAMP_IO | QDSP6v56_CLAMP_WL |
+ writel_relaxed(val, qproc->reg_base + QDSP6SS_PWR_CTL_REG);
+ pil_mss_restart_reg(qproc, 1);
And by using the reset framework for mss_restart this will fall out of
the conditional segment and the else is gone.
As i informed MSS RESET REGISTER was never a block control reset or BCR (a
term used to define those reset register which control a clock or pll ) so
clock control reset framework can not be used to do reset programming for
But MSS RESET is a "reset" and far as this driver is concerned it should
be abstracted by the help of the reset framework. I don't want this
driver to care about the workings of the reset control.

The peripheral resets are part of the GCC block and as such I do not see
the problem with having the driver for the GCC block expose these
resets, even if though it's not a BCR - and this is how we have done it
on 8960, 8974 and 8084 so far.
I was under impression that clock code will be up streamed by clock team, and they will go by downstream way.
i discussed again they said i can use GCC reset framework in upstream.
Will change patch accordingly.

that is why i have adopted IOREMAP based mss reset programming. it is like
any other register, may i know if any serious objection on using reset
controller framework only? i will have to add another dummy driver just to
do reset register programming.
let me know please if it is mandatory?
I want this driver to consume a reset from a reset-controller, I do not
see the technical reason why we cannot just add this to the driver for
the GCC block.
Sure, will do.