pr_debug("omap_hwmod: %s: enabling\n", oh->name);
/*
- * hwmods with HWMOD_INIT_NO_IDLE flag set are left
- * in enabled state at init.
- * Now that someone is really trying to enable them,
- * just ensure that the hwmod mux is set.
+ * hwmods with HWMOD_INIT_NO_IDLE flag set are left in enabled
+ * state at init. Now that someone is really trying to enable
+ * them, just ensure that the hwmod mux is set.
*/
if (oh->_int_flags & _HWMOD_SKIP_ENABLE) {
/*
}
/**
- * _setup - do initial configuration of omap_hwmod
+ * _setup_iclk_autoidle - configure an IP block's interface clocks
* @oh: struct omap_hwmod *
*
- * Writes the CLOCKACTIVITY bits @clockact to the hwmod @oh
- * OCP_SYSCONFIG register. Returns 0.
+ * Set up the module's interface clocks. XXX This function is still mostly
+ * a stub; implementing this properly requires iclk autoidle usecounting in
+ * the clock code. No return value.
*/
-static int _setup(struct omap_hwmod *oh, void *data)
+static void __init _setup_iclk_autoidle(struct omap_hwmod *oh)
{
- int i, r;
- u8 postsetup_state;
+ int i;
if (oh->_state != _HWMOD_STATE_INITIALIZED)
- return 0;
+ return;
- /* Set iclk autoidle mode */
- if (oh->slaves_cnt > 0) {
- for (i = 0; i < oh->slaves_cnt; i++) {
- struct omap_hwmod_ocp_if *os = oh->slaves[i];
- struct clk *c = os->_clk;
+ for (i = 0; i < oh->slaves_cnt; i++) {
+ struct omap_hwmod_ocp_if *os = oh->slaves[i];
+ struct clk *c = os->_clk;
- if (!c)
- continue;
+ if (!c)
+ continue;
- if (os->flags & OCPIF_SWSUP_IDLE) {
- /* XXX omap_iclk_deny_idle(c); */
- } else {
- /* XXX omap_iclk_allow_idle(c); */
- clk_enable(c);
- }
+ if (os->flags & OCPIF_SWSUP_IDLE) {
+ /* XXX omap_iclk_deny_idle(c); */
+ } else {
+ /* XXX omap_iclk_allow_idle(c); */
+ clk_enable(c);
}
}
- oh->_state = _HWMOD_STATE_INITIALIZED;
+ return;
+}
+
+/**
+ * _setup_reset - reset an IP block during the setup process
+ * @oh: struct omap_hwmod *
+ *
+ * Reset the IP block corresponding to the hwmod @oh during the setup
+ * process. The IP block is first enabled so it can be successfully
+ * reset. Returns 0 upon success or a negative error code upon
+ * failure.
+ */
+static int __init _setup_reset(struct omap_hwmod *oh)
+{
+ int r;
+
+ if (oh->_state != _HWMOD_STATE_INITIALIZED)
+ return -EINVAL;
/*
* In the case of hwmod with hardreset that should not be
* de-assert at boot time, we have to keep the module
* initialized, because we cannot enable it properly with the
- * reset asserted. Exit without warning because that behavior is
- * expected.
+ * reset asserted. Exit without warning because that behavior
+ * is expected.
*/
if ((oh->flags & HWMOD_INIT_NO_RESET) && oh->rst_lines_cnt > 0)
return 0;
}
if (!(oh->flags & HWMOD_INIT_NO_RESET))
- _reset(oh);
+ r = _reset(oh);
+
+ return r;
+}
+
+/**
+ * _setup_postsetup - transition to the appropriate state after _setup
+ * @oh: struct omap_hwmod *
+ *
+ * Place an IP block represented by @oh into a "post-setup" state --
+ * either IDLE, ENABLED, or DISABLED. ("post-setup" simply means that
+ * this function is called at the end of _setup().) The postsetup
+ * state for an IP block can be changed by calling
+ * omap_hwmod_enter_postsetup_state() early in the boot process,
+ * before one of the omap_hwmod_setup*() functions are called for the
+ * IP block.
+ *
+ * The IP block stays in this state until a PM runtime-based driver is
+ * loaded for that IP block. A post-setup state of IDLE is
+ * appropriate for almost all IP blocks with runtime PM-enabled
+ * drivers, since those drivers are able to enable the IP block. A
+ * post-setup state of ENABLED is appropriate for kernels with PM
+ * runtime disabled. The DISABLED state is appropriate for unusual IP
+ * blocks such as the MPU WDTIMER on kernels without WDTIMER drivers
+ * included, since the WDTIMER starts running on reset and will reset
+ * the MPU if left active.
+ *
+ * This post-setup mechanism is deprecated. Once all of the OMAP
+ * drivers have been converted to use PM runtime, and all of the IP
+ * block data and interconnect data is available to the hwmod code, it
+ * should be possible to replace this mechanism with a "lazy reset"
+ * arrangement. In a "lazy reset" setup, each IP block is enabled
+ * when the driver first probes, then all remaining IP blocks without
+ * drivers are either shut down or enabled after the drivers have
+ * loaded. However, this cannot take place until the above
+ * preconditions have been met, since otherwise the late reset code
+ * has no way of knowing which IP blocks are in use by drivers, and
+ * which ones are unused.
+ *
+ * No return value.
+ */
+static void __init _setup_postsetup(struct omap_hwmod *oh)
+{
+ u8 postsetup_state;
+
+ if (oh->rst_lines_cnt > 0)
+ return;
postsetup_state = oh->_postsetup_state;
if (postsetup_state == _HWMOD_STATE_UNKNOWN)
WARN(1, "hwmod: %s: unknown postsetup state %d! defaulting to enabled\n",
oh->name, postsetup_state);
+ return;
+}
+
+/**
+ * _setup - prepare IP block hardware for use
+ * @oh: struct omap_hwmod *
+ * @n: (unused, pass NULL)
+ *
+ * Configure the IP block represented by @oh. This may include
+ * enabling the IP block, resetting it, and placing it into a
+ * post-setup state, depending on the type of IP block and applicable
+ * flags. IP blocks are reset to prevent any previous configuration
+ * by the bootloader or previous operating system from interfering
+ * with power management or other parts of the system. The reset can
+ * be avoided; see omap_hwmod_no_setup_reset(). This is the second of
+ * two phases for hwmod initialization. Code called here generally
+ * affects the IP block hardware, or system integration hardware
+ * associated with the IP block. Returns 0.
+ */
+static int __init _setup(struct omap_hwmod *oh, void *data)
+{
+ if (oh->_state != _HWMOD_STATE_INITIALIZED)
+ return 0;
+
+ _setup_iclk_autoidle(oh);
+
+ if (!_setup_reset(oh))
+ _setup_postsetup(oh);
+
return 0;
}
* @state: state that _setup() should leave the hwmod in
*
* Sets the hwmod state that @oh will enter at the end of _setup()
- * (called by omap_hwmod_setup_*()). Only valid to call between
- * calling omap_hwmod_register() and omap_hwmod_setup_*(). Returns
- * 0 upon success or -EINVAL if there is a problem with the arguments
- * or if the hwmod is in the wrong state.
+ * (called by omap_hwmod_setup_*()). See also the documentation
+ * for _setup_postsetup(), above. Returns 0 upon success or
+ * -EINVAL if there is a problem with the arguments or if the hwmod is
+ * in the wrong state.
*/
int omap_hwmod_set_postsetup_state(struct omap_hwmod *oh, u8 state)
{
projects / users / hch / dma-mapping.git / commitdiff