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-rw-r--r--arch/arm/mach-keystone/psc.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/arm/mach-keystone/psc.c b/arch/arm/mach-keystone/psc.c
index 8991e23..ff042a6 100644
--- a/arch/arm/mach-keystone/psc.c
+++ b/arch/arm/mach-keystone/psc.c
@@ -233,3 +233,107 @@ int psc_disable_domain(u32 domain_num)
return psc_wait(domain_num);
}
+
+/**
+ * psc_module_keep_in_reset_enabled() - Keep module in enabled,in-reset state
+ * @mod_num: LPSC module number
+ * @gate_clocks: Can the clocks be gated on this module?
+ *
+ * Enable the module, but do not release the module from local reset. This is
+ * necessary for many processor systems on keystone SoCs to allow for system
+ * initialization from a master processor prior to releasing the processor
+ * from reset.
+ */
+int psc_module_keep_in_reset_enabled(u32 mod_num, bool gate_clocks)
+{
+ u32 mdctl, ptcmd, mdstat;
+ u32 next_state;
+ int domain_num = psc_get_domain_num(mod_num);
+ int timeout = 100000;
+
+ /* Wait for any previous transitions to complete */
+ psc_wait(domain_num);
+ mdctl = __raw_readl(KS2_PSC_BASE + PSC_REG_MDCTL(mod_num));
+ /* Should be set 0 to assert Local reset */
+ if ((mdctl & PSC_REG_MDCTL_SET_LRSTZ(mdctl, 1))) {
+ mdctl = PSC_REG_MDCTL_SET_LRSTZ(mdctl, 0);
+ __raw_writel(mdctl, KS2_PSC_BASE + PSC_REG_MDCTL(mod_num));
+ /* Wait for transition to take place */
+ psc_wait(domain_num);
+ }
+
+ /* Clear Module reset */
+ mdctl = __raw_readl(KS2_PSC_BASE + PSC_REG_MDCTL(mod_num));
+ next_state = gate_clocks ? PSC_REG_VAL_MDCTL_NEXT_OFF :
+ PSC_REG_VAL_MDCTL_NEXT_ON;
+ mdctl = PSC_REG_MDCTL_SET_NEXT(mdctl, next_state);
+ __raw_writel(mdctl, KS2_PSC_BASE + PSC_REG_MDCTL(mod_num));
+ /* Trigger PD transition */
+ ptcmd = __raw_readl(KS2_PSC_BASE + PSC_REG_PTCMD);
+ ptcmd |= (u32)(1 << domain_num);
+ __raw_writel(ptcmd, KS2_PSC_BASE + PSC_REG_PTCMD);
+ psc_wait(domain_num);
+
+ mdstat = __raw_readl(KS2_PSC_BASE + PSC_REG_MDSTAT(mod_num));
+ while (timeout) {
+ mdstat = __raw_readl(KS2_PSC_BASE + PSC_REG_MDSTAT(mod_num));
+
+ if (!(PSC_REG_MDSTAT_GET_STATUS(mdstat) & 0x30) &&
+ PSC_REG_MDSTAT_GET_MRSTDONE(mdstat) &&
+ PSC_REG_MDSTAT_GET_LRSTDONE(mdstat))
+ break;
+ timeout--;
+ }
+
+ if (!timeout) {
+ printf("%s: Timedout waiting for mdstat(0x%08x) to change\n",
+ __func__, mdstat);
+ return -ETIMEDOUT;
+ }
+ return 0;
+}
+
+/**
+ * psc_module_release_from_reset() - Release the module from reset
+ * @mod_num: LPSC module number
+ *
+ * This is the follow through for the command 'psc_module_keep_in_reset_enabled'
+ * Allowing the module to be released from reset once all required inits are
+ * complete for the module. Typically, this allows the processor module to start
+ * execution.
+ */
+int psc_module_release_from_reset(u32 mod_num)
+{
+ u32 mdctl, mdstat;
+ int domain_num = psc_get_domain_num(mod_num);
+ int timeout = 100000;
+
+ /* Wait for any previous transitions to complete */
+ psc_wait(domain_num);
+ mdctl = __raw_readl(KS2_PSC_BASE + PSC_REG_MDCTL(mod_num));
+ /* Should be set to 1 to de-assert Local reset */
+ if ((mdctl & PSC_REG_MDCTL_SET_LRSTZ(mdctl, 0))) {
+ mdctl = PSC_REG_MDCTL_SET_LRSTZ(mdctl, 1);
+ __raw_writel(mdctl, KS2_PSC_BASE + PSC_REG_MDCTL(mod_num));
+ /* Wait for transition to take place */
+ psc_wait(domain_num);
+ }
+ mdstat = __raw_readl(KS2_PSC_BASE + PSC_REG_MDSTAT(mod_num));
+ while (timeout) {
+ mdstat = __raw_readl(KS2_PSC_BASE + PSC_REG_MDSTAT(mod_num));
+
+ if (!(PSC_REG_MDSTAT_GET_STATUS(mdstat) & 0x30) &&
+ PSC_REG_MDSTAT_GET_MRSTDONE(mdstat) &&
+ PSC_REG_MDSTAT_GET_LRSTDONE(mdstat))
+ break;
+ timeout--;
+ }
+
+ if (!timeout) {
+ printf("%s: Timedout waiting for mdstat(0x%08x) to change\n",
+ __func__, mdstat);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}