[PATCH v2 8/8] imx_dsp_rproc: Use reset controller API to control the DSP

Daniel Baluta
2025-02-19T19:21:40Z

Use the reset controller API to control the DSP on i.MX8MP. This way
we can have a better control of the resources and avoid using a syscon
to access the audiomix bits.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
---
drivers/remoteproc/imx_dsp_rproc.c | 25 +++++++++++++++++--------
drivers/remoteproc/imx_rproc.h | 2 ++
2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/remoteproc/imx_dsp_rproc.c b/drivers/remoteproc/imx_dsp_rproc.c
index ea5024919c2f..631563e4f86d 100644
--- a/drivers/remoteproc/imx_dsp_rproc.c
+++ b/drivers/remoteproc/imx_dsp_rproc.c
@@ -19,6 +19,7 @@
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/remoteproc.h>
+#include <linux/reset.h>
#include <linux/slab.h>

#include "imx_rproc.h"
@@ -111,6 +112,7 @@ enum imx_dsp_rp_mbox_messages {
*/
struct imx_dsp_rproc {
struct regmap *regmap;
+ struct reset_control *reset;
struct rproc *rproc;
const struct imx_dsp_rproc_dcfg *dsp_dcfg;
struct clk_bulk_data clks[DSP_RPROC_CLK_MAX];
@@ -192,9 +194,7 @@ static int imx8mp_dsp_reset(struct imx_dsp_rproc *priv)
/* Keep reset asserted for 10 cycles */
usleep_range(1, 2);

- regmap_update_bits(priv->regmap, IMX8M_AudioDSP_REG2,
- IMX8M_AudioDSP_REG2_RUNSTALL,
- IMX8M_AudioDSP_REG2_RUNSTALL);
+ reset_control_assert(priv->reset);

/* Take the DSP out of reset and keep stalled for FW loading */
pwrctl = readl(dap + IMX8M_DAP_PWRCTL);
@@ -231,13 +231,9 @@ static int imx8ulp_dsp_reset(struct imx_dsp_rproc *priv)

/* Specific configuration for i.MX8MP */
static const struct imx_rproc_dcfg dsp_rproc_cfg_imx8mp = {
- .src_reg = IMX8M_AudioDSP_REG2,
- .src_mask = IMX8M_AudioDSP_REG2_RUNSTALL,
- .src_start = 0,
- .src_stop = IMX8M_AudioDSP_REG2_RUNSTALL,
.att = imx_dsp_rproc_att_imx8mp,
.att_size = ARRAY_SIZE(imx_dsp_rproc_att_imx8mp),
- .method = IMX_RPROC_MMIO,
+ .method = IMX_RPROC_RESET_CONTROLLER,
};

static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8mp = {
@@ -329,6 +325,9 @@ static int imx_dsp_rproc_start(struct rproc *rproc)
true,
rproc->bootaddr);
break;
+ case IMX_RPROC_RESET_CONTROLLER:
+ ret = reset_control_deassert(priv->reset);
+ break;
default:
return -EOPNOTSUPP;
}
@@ -369,6 +368,9 @@ static int imx_dsp_rproc_stop(struct rproc *rproc)
false,
rproc->bootaddr);
break;
+ case IMX_RPROC_RESET_CONTROLLER:
+ ret = reset_control_assert(priv->reset);
+ break;
default:
return -EOPNOTSUPP;
}
@@ -995,6 +997,13 @@ static int imx_dsp_rproc_detect_mode(struct imx_dsp_rproc *priv)

priv->regmap = regmap;
break;
+ case IMX_RPROC_RESET_CONTROLLER:
+ priv->reset = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(priv->reset)) {
+ dev_err(dev, "Failed to get DSP reset control\n");
+ return PTR_ERR(priv->reset);
+ }
+ break;
default:
ret = -EOPNOTSUPP;
break;
diff --git a/drivers/remoteproc/imx_rproc.h b/drivers/remoteproc/imx_rproc.h
index 17a7d051c531..cfd38d37e146 100644
--- a/drivers/remoteproc/imx_rproc.h
+++ b/drivers/remoteproc/imx_rproc.h
@@ -24,6 +24,8 @@ enum imx_rproc_method {
IMX_RPROC_SMC,
/* Through System Control Unit API */
IMX_RPROC_SCU_API,
+ /* Through Reset Controller API */
+ IMX_RPROC_RESET_CONTROLLER,
};

/* dcfg flags */
--
2.25.1