mfd: db8500 OPP and sleep handling update
This updates the operating point handling code by:
- Supporting the DDR OPP retention state.
- Supporting another low operating point named
APE_50_PARTLY_25_OPP
- Adding an interface to figure out if the sleep state change
was properly achieved.
Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Mattias Nilsson <mattias.i.nilsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c
index 1385639..8056968 100644
--- a/drivers/mfd/db8500-prcmu.c
+++ b/drivers/mfd/db8500-prcmu.c
@@ -343,11 +343,13 @@
* mb1_transfer - state needed for mailbox 1 communication.
* @lock: The transaction lock.
* @work: The transaction completion structure.
+ * @ape_opp: The current APE OPP.
* @ack: Reply ("acknowledge") data.
*/
static struct {
struct mutex lock;
struct completion work;
+ u8 ape_opp;
struct {
u8 header;
u8 arm_opp;
@@ -816,6 +818,11 @@
return 0;
}
+u8 db8500_prcmu_get_power_state_result(void)
+{
+ return readb(tcdm_base + PRCM_ACK_MB0_AP_PWRSTTR_STATUS);
+}
+
/* This function should only be called while mb0_transfer.lock is held. */
static void config_wakeups(void)
{
@@ -965,6 +972,52 @@
return 0;
}
+/* Divide the frequency of certain clocks by 2 for APE_50_PARTLY_25_OPP. */
+static void request_even_slower_clocks(bool enable)
+{
+ void __iomem *clock_reg[] = {
+ PRCM_ACLK_MGT,
+ PRCM_DMACLK_MGT
+ };
+ unsigned long flags;
+ unsigned int i;
+
+ spin_lock_irqsave(&clk_mgt_lock, flags);
+
+ /* Grab the HW semaphore. */
+ while ((readl(PRCM_SEM) & PRCM_SEM_PRCM_SEM) != 0)
+ cpu_relax();
+
+ for (i = 0; i < ARRAY_SIZE(clock_reg); i++) {
+ u32 val;
+ u32 div;
+
+ val = readl(clock_reg[i]);
+ div = (val & PRCM_CLK_MGT_CLKPLLDIV_MASK);
+ if (enable) {
+ if ((div <= 1) || (div > 15)) {
+ pr_err("prcmu: Bad clock divider %d in %s\n",
+ div, __func__);
+ goto unlock_and_return;
+ }
+ div <<= 1;
+ } else {
+ if (div <= 2)
+ goto unlock_and_return;
+ div >>= 1;
+ }
+ val = ((val & ~PRCM_CLK_MGT_CLKPLLDIV_MASK) |
+ (div & PRCM_CLK_MGT_CLKPLLDIV_MASK));
+ writel(val, clock_reg[i]);
+ }
+
+unlock_and_return:
+ /* Release the HW semaphore. */
+ writel(0, PRCM_SEM);
+
+ spin_unlock_irqrestore(&clk_mgt_lock, flags);
+}
+
/**
* db8500_set_ape_opp - set the appropriate APE OPP
* @opp: The new APE operating point to which transition is to be made
@@ -976,14 +1029,24 @@
{
int r = 0;
+ if (opp == mb1_transfer.ape_opp)
+ return 0;
+
mutex_lock(&mb1_transfer.lock);
+ if (mb1_transfer.ape_opp == APE_50_PARTLY_25_OPP)
+ request_even_slower_clocks(false);
+
+ if ((opp != APE_100_OPP) && (mb1_transfer.ape_opp != APE_100_OPP))
+ goto skip_message;
+
while (readl(PRCM_MBOX_CPU_VAL) & MBOX_BIT(1))
cpu_relax();
writeb(MB1H_ARM_APE_OPP, (tcdm_base + PRCM_MBOX_HEADER_REQ_MB1));
writeb(ARM_NO_CHANGE, (tcdm_base + PRCM_REQ_MB1_ARM_OPP));
- writeb(opp, (tcdm_base + PRCM_REQ_MB1_APE_OPP));
+ writeb(((opp == APE_50_PARTLY_25_OPP) ? APE_50_OPP : opp),
+ (tcdm_base + PRCM_REQ_MB1_APE_OPP));
writel(MBOX_BIT(1), PRCM_MBOX_CPU_SET);
wait_for_completion(&mb1_transfer.work);
@@ -992,6 +1055,13 @@
(mb1_transfer.ack.ape_opp != opp))
r = -EIO;
+skip_message:
+ if ((!r && (opp == APE_50_PARTLY_25_OPP)) ||
+ (r && (mb1_transfer.ape_opp == APE_50_PARTLY_25_OPP)))
+ request_even_slower_clocks(true);
+ if (!r)
+ mb1_transfer.ape_opp = opp;
+
mutex_unlock(&mb1_transfer.lock);
return r;
@@ -2631,6 +2701,7 @@
init_completion(&mb0_transfer.ac_wake_work);
mutex_init(&mb1_transfer.lock);
init_completion(&mb1_transfer.work);
+ mb1_transfer.ape_opp = APE_NO_CHANGE;
mutex_init(&mb2_transfer.lock);
init_completion(&mb2_transfer.work);
spin_lock_init(&mb2_transfer.auto_pm_lock);