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Diffstat (limited to 'drivers/soc/ti/pruss.c')
-rw-r--r--drivers/soc/ti/pruss.c81
1 files changed, 79 insertions, 2 deletions
diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c
index 56e0ac948796..b373d5579647 100644
--- a/drivers/soc/ti/pruss.c
+++ b/drivers/soc/ti/pruss.c
@@ -22,14 +22,19 @@
#include <linux/remoteproc.h>
#include <linux/slab.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;
};
/**
@@ -205,6 +210,72 @@ int pruss_cfg_update(struct pruss *pruss, unsigned int reg,
}
EXPORT_SYMBOL_GPL(pruss_cfg_update);
+/**
+ * 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)
+{
+ int ret;
+ u32 syscfg_val, i;
+ const struct pruss_private_data *data;
+
+ 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;
@@ -487,10 +558,16 @@ static int pruss_remove(struct platform_device *pdev)
/* instance-specific driver private data */
static const struct pruss_private_data am437x_pruss1_data = {
.has_no_sharedram = false,
+ .has_ocp_syscfg = true,
};
static const struct pruss_private_data am437x_pruss0_data = {
.has_no_sharedram = true,
+ .has_ocp_syscfg = false,
+};
+
+static const struct pruss_private_data am33xx_am57xx_data = {
+ .has_ocp_syscfg = true,
};
static const struct pruss_private_data am65x_j721e_pruss_data = {
@@ -498,10 +575,10 @@ static const struct pruss_private_data am65x_j721e_pruss_data = {
};
static const struct of_device_id pruss_of_match[] = {
- { .compatible = "ti,am3356-pruss" },
+ { .compatible = "ti,am3356-pruss", .data = &am33xx_am57xx_data },
{ .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 = &am33xx_am57xx_data },
{ .compatible = "ti,k2g-pruss" },
{ .compatible = "ti,am654-icssg", .data = &am65x_j721e_pruss_data, },
{ .compatible = "ti,j721e-icssg", .data = &am65x_j721e_pruss_data, },