From 4d64d2e34bc415b05eb77a2732a3164313cf6de3 Mon Sep 17 00:00:00 2001 From: Mattias Nilsson Date: Fri, 13 Jan 2012 16:20:43 +0100 Subject: 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 Signed-off-by: Rabin Vincent Signed-off-by: Mattias Nilsson Signed-off-by: Linus Walleij Signed-off-by: Samuel Ortiz --- drivers/mfd/db8500-prcmu.c | 73 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 72 insertions(+), 1 deletion(-) (limited to 'drivers/mfd/db8500-prcmu.c') diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c index 13856392cb27..8056968da20f 100644 --- a/drivers/mfd/db8500-prcmu.c +++ b/drivers/mfd/db8500-prcmu.c @@ -343,11 +343,13 @@ static struct { * 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 @@ int db8500_prcmu_set_power_state(u8 state, bool keep_ulp_clk, bool keep_ap_pll) 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 @@ int db8500_prcmu_set_ddr_opp(u8 opp) 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 db8500_prcmu_set_ape_opp(u8 opp) { 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 @@ int db8500_prcmu_set_ape_opp(u8 opp) (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 @@ void __init db8500_prcmu_early_init(void) 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); -- cgit v1.2.3-59-g8ed1b