[PATCH v4 5/5] remoteproc: qcom: Always assert and deassert reset signals in SDM845

From: Sibi Sankar
Date: Wed Apr 25 2018 - 11:09:54 EST


SDM845 brings a new reset signal ALT_RESET which is a part of the MSS
subsystem hence requires some of the active clks to be enabled before
assert/deassert

Reset the modem if the BOOT FSM does timeout

Reset assert/deassert sequence vary across SoCs adding reset, adding
start/stop helper functions to handle SoC specific reset sequences

Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
---
drivers/remoteproc/qcom_q6v5_pil.c | 81 ++++++++++++++++++++++++++++--
1 file changed, 76 insertions(+), 5 deletions(-)

diff --git a/drivers/remoteproc/qcom_q6v5_pil.c b/drivers/remoteproc/qcom_q6v5_pil.c
index 4d9504e8bf8e..99ef3f51c528 100644
--- a/drivers/remoteproc/qcom_q6v5_pil.c
+++ b/drivers/remoteproc/qcom_q6v5_pil.c
@@ -130,9 +130,11 @@ struct rproc_hexagon_res {
struct qcom_mss_reg_res *proxy_supply;
struct qcom_mss_reg_res *active_supply;
char **proxy_clk_names;
+ char **reset_clk_names;
char **active_clk_names;
int version;
bool need_mem_protection;
+ bool has_alt_reset;
};

struct q6v5 {
@@ -157,8 +159,10 @@ struct q6v5 {
unsigned int fatal_interrupt;

struct clk *active_clks[8];
+ struct clk *reset_clks[4];
struct clk *proxy_clks[4];
int active_clk_count;
+ int reset_clk_count;
int proxy_clk_count;

struct reg_info active_regs[1];
@@ -179,6 +183,9 @@ struct q6v5 {
void *mpss_region;
size_t mpss_size;

+ int (*reset_deassert)(struct q6v5 *qproc);
+ int (*reset_assert)(struct q6v5 *qproc);
+
struct qcom_rproc_glink glink_subdev;
struct qcom_rproc_subdev smd_subdev;
struct qcom_rproc_ssr ssr_subdev;
@@ -349,6 +356,32 @@ static int q6v5_load(struct rproc *rproc, const struct firmware *fw)
return 0;
}

+static int q6v5_reset_assert(struct q6v5 *qproc)
+{
+ return reset_control_assert(qproc->mss_restart);
+}
+
+static int q6v5_reset_deassert(struct q6v5 *qproc)
+{
+ return reset_control_deassert(qproc->mss_restart);
+}
+
+static int q6v5_alt_reset_assert(struct q6v5 *qproc)
+{
+ return reset_control_reset(qproc->mss_restart);
+}
+
+static int q6v5_alt_reset_deassert(struct q6v5 *qproc)
+{
+ /* Ensure alt reset is written before restart reg */
+ writel(1, qproc->rmb_base + RMB_MBA_ALT_RESET);
+
+ reset_control_reset(qproc->mss_restart);
+
+ writel(0, qproc->rmb_base + RMB_MBA_ALT_RESET);
+ return 0;
+}
+
static int q6v5_rmb_pbl_wait(struct q6v5 *qproc, int ms)
{
unsigned long timeout;
@@ -424,6 +457,8 @@ static int q6v5proc_reset(struct q6v5 *qproc)
val, (val & BIT(0)) != 0, 10, BOOT_FSM_TIMEOUT);
if (ret) {
dev_err(qproc->dev, "Boot FSM failed to complete.\n");
+ /* Reset the modem so that boot FSM is in reset state */
+ qproc->reset_deassert(qproc);
return ret;
}

@@ -792,12 +827,20 @@ static int q6v5_start(struct rproc *rproc)
dev_err(qproc->dev, "failed to enable supplies\n");
goto disable_proxy_clk;
}
- ret = reset_control_deassert(qproc->mss_restart);
+
+ ret = q6v5_clk_enable(qproc->dev, qproc->reset_clks,
+ qproc->reset_clk_count);
if (ret) {
- dev_err(qproc->dev, "failed to deassert mss restart\n");
+ dev_err(qproc->dev, "failed to enable reset clocks\n");
goto disable_vdd;
}

+ ret = qproc->reset_deassert(qproc);
+ if (ret) {
+ dev_err(qproc->dev, "failed to deassert mss restart\n");
+ goto disable_reset_clks;
+ }
+
ret = q6v5_clk_enable(qproc->dev, qproc->active_clks,
qproc->active_clk_count);
if (ret) {
@@ -888,7 +931,10 @@ static int q6v5_start(struct rproc *rproc)
qproc->active_clk_count);

assert_reset:
- reset_control_assert(qproc->mss_restart);
+ qproc->reset_assert(qproc);
+disable_reset_clks:
+ q6v5_clk_disable(qproc->dev, qproc->reset_clks,
+ qproc->reset_clk_count);
disable_vdd:
q6v5_regulator_disable(qproc, qproc->active_regs,
qproc->active_reg_count);
@@ -938,7 +984,7 @@ static int q6v5_stop(struct rproc *rproc)
qproc->mpss_phys, qproc->mpss_size);
WARN_ON(ret);

- reset_control_assert(qproc->mss_restart);
+ qproc->reset_assert(qproc);
disable_irq(qproc->handover_interrupt);
if (!qproc->unvoted_flag) {
q6v5_clk_disable(qproc->dev, qproc->proxy_clks,
@@ -949,6 +995,8 @@ static int q6v5_stop(struct rproc *rproc)
disable_irq(qproc->wdog_interrupt);
disable_irq(qproc->fatal_interrupt);

+ q6v5_clk_disable(qproc->dev, qproc->reset_clks,
+ qproc->reset_clk_count);
q6v5_clk_disable(qproc->dev, qproc->active_clks,
qproc->active_clk_count);
q6v5_regulator_disable(qproc, qproc->active_regs,
@@ -1211,6 +1259,14 @@ static int q6v5_probe(struct platform_device *pdev)
qproc->rproc = rproc;
platform_set_drvdata(pdev, qproc);

+ if (desc->has_alt_reset) {
+ qproc->reset_deassert = q6v5_alt_reset_deassert;
+ qproc->reset_assert = q6v5_alt_reset_assert;
+ } else {
+ qproc->reset_deassert = q6v5_reset_deassert;
+ qproc->reset_assert = q6v5_reset_assert;
+ }
+
init_completion(&qproc->start_done);
init_completion(&qproc->stop_done);

@@ -1230,6 +1286,14 @@ static int q6v5_probe(struct platform_device *pdev)
}
qproc->proxy_clk_count = ret;

+ ret = q6v5_init_clocks(&pdev->dev, qproc->reset_clks,
+ desc->reset_clk_names);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to get reset clocks.\n");
+ goto free_rproc;
+ }
+ qproc->reset_clk_count = ret;
+
ret = q6v5_init_clocks(&pdev->dev, qproc->active_clks,
desc->active_clk_names);
if (ret < 0) {
@@ -1335,8 +1399,11 @@ static const struct rproc_hexagon_res sdm845_mss = {
"prng",
NULL
},
- .active_clk_names = (char*[]){
+ .reset_clk_names = (char*[]){
"iface",
+ NULL
+ },
+ .active_clk_names = (char*[]){
"bus",
"mem",
"gpll0_mss",
@@ -1345,6 +1412,7 @@ static const struct rproc_hexagon_res sdm845_mss = {
NULL
},
.need_mem_protection = true,
+ .has_alt_reset = true,
.version = MSS_SDM845,
};

@@ -1363,6 +1431,7 @@ static const struct rproc_hexagon_res msm8996_mss = {
NULL
},
.need_mem_protection = true,
+ .has_alt_reset = false,
.version = MSS_MSM8996,
};

@@ -1394,6 +1463,7 @@ static const struct rproc_hexagon_res msm8916_mss = {
NULL
},
.need_mem_protection = false,
+ .has_alt_reset = false,
.version = MSS_MSM8916,
};

@@ -1433,6 +1503,7 @@ static const struct rproc_hexagon_res msm8974_mss = {
NULL
},
.need_mem_protection = false,
+ .has_alt_reset = false,
.version = MSS_MSM8974,
};

--
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