From: Roger Quadros <rogerq@xxxxxx>
Updates OCP master port configuration to enable memory access outside
of the PRU-ICSS subsystem.
This set of changes configures PRUSS_SYSCFG.STANDBY_INIT bit either
to enable or disable the OCP master ports (applicable only on SoCs
using OCP interconnect like the OMAP family).
Signed-off-by: Roger Quadros <rogerq@xxxxxx>
Signed-off-by: Andrew F. Davis <afd@xxxxxx>
Signed-off-by: Parvathi Pudi <parvathi@xxxxxxxxxxx>
Signed-off-by: Basharath Hussain Khaja <basharath@xxxxxxxxxxx>
---
drivers/soc/ti/pruss.c | 77 +++++++++++++++++++++++++++++++++++-
include/linux/pruss_driver.h | 6 +++
2 files changed, 82 insertions(+), 1 deletion(-)
diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c
index d7634bf5413a..a0e233da052c 100644
--- a/drivers/soc/ti/pruss.c
+++ b/drivers/soc/ti/pruss.c
@@ -25,14 +25,19 @@
#include <linux/slab.h>
#include "pruss.h"
+#define SYSCFG_STANDBY_INIT BIT(4)
+#define SYSCFG_SUB_MWAIT_READY BIT(5)
+
/**
* struct pruss_private_data - PRUSS driver private data
* @has_no_sharedram: flag to indicate the absence of PRUSS Shared Data RAM
* @has_core_mux_clock: flag to indicate the presence of PRUSS core clock
+ * @has_ocp_syscfg: flag to indicate if OCP SYSCFG is present
*/
struct pruss_private_data {
bool has_no_sharedram;
bool has_core_mux_clock;
+ bool has_ocp_syscfg;
};
/**
@@ -286,6 +291,72 @@ int pruss_cfg_xfr_enable(struct pruss *pruss, enum pru_type pru_type,
}
EXPORT_SYMBOL_GPL(pruss_cfg_xfr_enable);
+/**
+ * pruss_cfg_ocp_master_ports() - configure PRUSS OCP master ports
+ * @pruss: the pruss instance handle
+ * @enable: set to true for enabling or false for disabling the OCP master ports
+ *
+ * This function programs the PRUSS_SYSCFG.STANDBY_INIT bit either to enable or
+ * disable the OCP master ports (applicable only on SoCs using OCP interconnect
+ * like the OMAP family). Clearing the bit achieves dual functionalities - one
+ * is to deassert the MStandby signal to the device PRCM, and the other is to
+ * enable OCP master ports to allow accesses outside of the PRU-ICSS. The
+ * function has to wait for the PRCM to acknowledge through the monitoring of
+ * the PRUSS_SYSCFG.SUB_MWAIT bit when enabling master ports. Setting the bit
+ * disables the master access, and also signals the PRCM that the PRUSS is ready
+ * for Standby.
+ *
+ * Return: 0 on success, or an error code otherwise. ETIMEDOUT is returned
+ * when the ready-state fails.
+ */
+int pruss_cfg_ocp_master_ports(struct pruss *pruss, bool enable)
+{
+ const struct pruss_private_data *data;
+ u32 syscfg_val, i;
+ int ret;
+
+ if (IS_ERR_OR_NULL(pruss))
+ return -EINVAL;
+
+ data = of_device_get_match_data(pruss->dev);
+
+ /* nothing to do on non OMAP-SoCs */
+ if (!data || !data->has_ocp_syscfg)
+ return 0;
+
+ /* assert the MStandby signal during disable path */
+ if (!enable)
+ return pruss_cfg_update(pruss, PRUSS_CFG_SYSCFG,
+ SYSCFG_STANDBY_INIT,
+ SYSCFG_STANDBY_INIT);
+
+ /* enable the OCP master ports and disable MStandby */
+ ret = pruss_cfg_update(pruss, PRUSS_CFG_SYSCFG, SYSCFG_STANDBY_INIT, 0);
+ if (ret)
+ return ret;
+
+ /* wait till we are ready for transactions - delay is arbitrary */
+ for (i = 0; i < 10; i++) {
+ ret = pruss_cfg_read(pruss, PRUSS_CFG_SYSCFG, &syscfg_val);
+ if (ret)
+ goto disable;
+
+ if (!(syscfg_val & SYSCFG_SUB_MWAIT_READY))
+ return 0;
+
+ udelay(5);
+ }
+
+ dev_err(pruss->dev, "timeout waiting for SUB_MWAIT_READY\n");
+ ret = -ETIMEDOUT;
+
+disable:
+ pruss_cfg_update(pruss, PRUSS_CFG_SYSCFG, SYSCFG_STANDBY_INIT,
+ SYSCFG_STANDBY_INIT);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pruss_cfg_ocp_master_ports);
+
static void pruss_of_free_clk_provider(void *data)
{
struct device_node *clk_mux_np = data;
@@ -570,6 +641,10 @@ static const struct pruss_private_data am437x_pruss0_data = {
.has_no_sharedram = true,
};
+static const struct pruss_private_data am57xx_data = {
+ .has_ocp_syscfg = true,
+};
+
static const struct pruss_private_data am65x_j721e_pruss_data = {
.has_core_mux_clock = true,
};
@@ -578,7 +653,7 @@ static const struct of_device_id pruss_of_match[] = {
{ .compatible = "ti,am3356-pruss" },
{ .compatible = "ti,am4376-pruss0", .data = &am437x_pruss0_data, },
{ .compatible = "ti,am4376-pruss1", .data = &am437x_pruss1_data, },
- { .compatible = "ti,am5728-pruss" },
+ { .compatible = "ti,am5728-pruss", .data = &am57xx_data, },
{ .compatible = "ti,k2g-pruss" },
{ .compatible = "ti,am654-icssg", .data = &am65x_j721e_pruss_data, },
{ .compatible = "ti,j721e-icssg", .data = &am65x_j721e_pruss_data, },
diff --git a/include/linux/pruss_driver.h b/include/linux/pruss_driver.h
index 2e18fef1a2e1..15b3c9c58539 100644
--- a/include/linux/pruss_driver.h
+++ b/include/linux/pruss_driver.h
@@ -118,6 +118,7 @@ int pruss_cfg_gpimode(struct pruss *pruss, enum pruss_pru_id pru_id,
int pruss_cfg_miirt_enable(struct pruss *pruss, bool enable);
int pruss_cfg_xfr_enable(struct pruss *pruss, enum pru_type pru_type,
bool enable);
+int pruss_cfg_ocp_master_ports(struct pruss *pruss, bool enable);
#else
@@ -172,6 +173,11 @@ static inline int pruss_cfg_xfr_enable(struct pruss *pruss,
return -EOPNOTSUPP;
}
+static int pruss_cfg_ocp_master_ports(struct pruss *pruss, bool enable)
+{
+ return -EOPNOTSUPP;
+}
+
#endif /* CONFIG_TI_PRUSS */
#endif /* _PRUSS_DRIVER_H_ */
--
2.34.1
