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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/video/fbdev/omap2/omapfb/dss/pll.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/video/fbdev/omap2/omapfb/dss/pll.c')
-rw-r--r--drivers/video/fbdev/omap2/omapfb/dss/pll.c378
1 files changed, 378 insertions, 0 deletions
diff --git a/drivers/video/fbdev/omap2/omapfb/dss/pll.c b/drivers/video/fbdev/omap2/omapfb/dss/pll.c
new file mode 100644
index 000000000..725194d52
--- /dev/null
+++ b/drivers/video/fbdev/omap2/omapfb/dss/pll.c
@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2014 Texas Instruments Incorporated
+ */
+
+#define DSS_SUBSYS_NAME "PLL"
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sched.h>
+
+#include <video/omapfb_dss.h>
+
+#include "dss.h"
+
+#define PLL_CONTROL 0x0000
+#define PLL_STATUS 0x0004
+#define PLL_GO 0x0008
+#define PLL_CONFIGURATION1 0x000C
+#define PLL_CONFIGURATION2 0x0010
+#define PLL_CONFIGURATION3 0x0014
+#define PLL_SSC_CONFIGURATION1 0x0018
+#define PLL_SSC_CONFIGURATION2 0x001C
+#define PLL_CONFIGURATION4 0x0020
+
+static struct dss_pll *dss_plls[4];
+
+int dss_pll_register(struct dss_pll *pll)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dss_plls); ++i) {
+ if (!dss_plls[i]) {
+ dss_plls[i] = pll;
+ return 0;
+ }
+ }
+
+ return -EBUSY;
+}
+
+void dss_pll_unregister(struct dss_pll *pll)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dss_plls); ++i) {
+ if (dss_plls[i] == pll) {
+ dss_plls[i] = NULL;
+ return;
+ }
+ }
+}
+
+struct dss_pll *dss_pll_find(const char *name)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dss_plls); ++i) {
+ if (dss_plls[i] && strcmp(dss_plls[i]->name, name) == 0)
+ return dss_plls[i];
+ }
+
+ return NULL;
+}
+
+int dss_pll_enable(struct dss_pll *pll)
+{
+ int r;
+
+ r = clk_prepare_enable(pll->clkin);
+ if (r)
+ return r;
+
+ if (pll->regulator) {
+ r = regulator_enable(pll->regulator);
+ if (r)
+ goto err_reg;
+ }
+
+ r = pll->ops->enable(pll);
+ if (r)
+ goto err_enable;
+
+ return 0;
+
+err_enable:
+ if (pll->regulator)
+ regulator_disable(pll->regulator);
+err_reg:
+ clk_disable_unprepare(pll->clkin);
+ return r;
+}
+
+void dss_pll_disable(struct dss_pll *pll)
+{
+ pll->ops->disable(pll);
+
+ if (pll->regulator)
+ regulator_disable(pll->regulator);
+
+ clk_disable_unprepare(pll->clkin);
+
+ memset(&pll->cinfo, 0, sizeof(pll->cinfo));
+}
+
+int dss_pll_set_config(struct dss_pll *pll, const struct dss_pll_clock_info *cinfo)
+{
+ int r;
+
+ r = pll->ops->set_config(pll, cinfo);
+ if (r)
+ return r;
+
+ pll->cinfo = *cinfo;
+
+ return 0;
+}
+
+bool dss_pll_hsdiv_calc(const struct dss_pll *pll, unsigned long clkdco,
+ unsigned long out_min, unsigned long out_max,
+ dss_hsdiv_calc_func func, void *data)
+{
+ const struct dss_pll_hw *hw = pll->hw;
+ int m, m_start, m_stop;
+ unsigned long out;
+
+ out_min = out_min ? out_min : 1;
+ out_max = out_max ? out_max : ULONG_MAX;
+
+ m_start = max(DIV_ROUND_UP(clkdco, out_max), 1ul);
+
+ m_stop = min((unsigned)(clkdco / out_min), hw->mX_max);
+
+ for (m = m_start; m <= m_stop; ++m) {
+ out = clkdco / m;
+
+ if (func(m, out, data))
+ return true;
+ }
+
+ return false;
+}
+
+bool dss_pll_calc(const struct dss_pll *pll, unsigned long clkin,
+ unsigned long pll_min, unsigned long pll_max,
+ dss_pll_calc_func func, void *data)
+{
+ const struct dss_pll_hw *hw = pll->hw;
+ int n, n_start, n_stop;
+ int m, m_start, m_stop;
+ unsigned long fint, clkdco;
+ unsigned long pll_hw_max;
+ unsigned long fint_hw_min, fint_hw_max;
+
+ pll_hw_max = hw->clkdco_max;
+
+ fint_hw_min = hw->fint_min;
+ fint_hw_max = hw->fint_max;
+
+ n_start = max(DIV_ROUND_UP(clkin, fint_hw_max), 1ul);
+ n_stop = min((unsigned)(clkin / fint_hw_min), hw->n_max);
+
+ pll_max = pll_max ? pll_max : ULONG_MAX;
+
+ for (n = n_start; n <= n_stop; ++n) {
+ fint = clkin / n;
+
+ m_start = max(DIV_ROUND_UP(DIV_ROUND_UP(pll_min, fint), 2),
+ 1ul);
+ m_stop = min3((unsigned)(pll_max / fint / 2),
+ (unsigned)(pll_hw_max / fint / 2),
+ hw->m_max);
+
+ for (m = m_start; m <= m_stop; ++m) {
+ clkdco = 2 * m * fint;
+
+ if (func(n, m, fint, clkdco, data))
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static int wait_for_bit_change(void __iomem *reg, int bitnum, int value)
+{
+ unsigned long timeout;
+ ktime_t wait;
+ int t;
+
+ /* first busyloop to see if the bit changes right away */
+ t = 100;
+ while (t-- > 0) {
+ if (FLD_GET(readl_relaxed(reg), bitnum, bitnum) == value)
+ return value;
+ }
+
+ /* then loop for 500ms, sleeping for 1ms in between */
+ timeout = jiffies + msecs_to_jiffies(500);
+ while (time_before(jiffies, timeout)) {
+ if (FLD_GET(readl_relaxed(reg), bitnum, bitnum) == value)
+ return value;
+
+ wait = ns_to_ktime(1000 * 1000);
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_hrtimeout(&wait, HRTIMER_MODE_REL);
+ }
+
+ return !value;
+}
+
+int dss_pll_wait_reset_done(struct dss_pll *pll)
+{
+ void __iomem *base = pll->base;
+
+ if (wait_for_bit_change(base + PLL_STATUS, 0, 1) != 1)
+ return -ETIMEDOUT;
+ else
+ return 0;
+}
+
+static int dss_wait_hsdiv_ack(struct dss_pll *pll, u32 hsdiv_ack_mask)
+{
+ int t = 100;
+
+ while (t-- > 0) {
+ u32 v = readl_relaxed(pll->base + PLL_STATUS);
+ v &= hsdiv_ack_mask;
+ if (v == hsdiv_ack_mask)
+ return 0;
+ }
+
+ return -ETIMEDOUT;
+}
+
+int dss_pll_write_config_type_a(struct dss_pll *pll,
+ const struct dss_pll_clock_info *cinfo)
+{
+ const struct dss_pll_hw *hw = pll->hw;
+ void __iomem *base = pll->base;
+ int r = 0;
+ u32 l;
+
+ l = 0;
+ if (hw->has_stopmode)
+ l = FLD_MOD(l, 1, 0, 0); /* PLL_STOPMODE */
+ l = FLD_MOD(l, cinfo->n - 1, hw->n_msb, hw->n_lsb); /* PLL_REGN */
+ l = FLD_MOD(l, cinfo->m, hw->m_msb, hw->m_lsb); /* PLL_REGM */
+ /* M4 */
+ l = FLD_MOD(l, cinfo->mX[0] ? cinfo->mX[0] - 1 : 0,
+ hw->mX_msb[0], hw->mX_lsb[0]);
+ /* M5 */
+ l = FLD_MOD(l, cinfo->mX[1] ? cinfo->mX[1] - 1 : 0,
+ hw->mX_msb[1], hw->mX_lsb[1]);
+ writel_relaxed(l, base + PLL_CONFIGURATION1);
+
+ l = 0;
+ /* M6 */
+ l = FLD_MOD(l, cinfo->mX[2] ? cinfo->mX[2] - 1 : 0,
+ hw->mX_msb[2], hw->mX_lsb[2]);
+ /* M7 */
+ l = FLD_MOD(l, cinfo->mX[3] ? cinfo->mX[3] - 1 : 0,
+ hw->mX_msb[3], hw->mX_lsb[3]);
+ writel_relaxed(l, base + PLL_CONFIGURATION3);
+
+ l = readl_relaxed(base + PLL_CONFIGURATION2);
+ if (hw->has_freqsel) {
+ u32 f = cinfo->fint < 1000000 ? 0x3 :
+ cinfo->fint < 1250000 ? 0x4 :
+ cinfo->fint < 1500000 ? 0x5 :
+ cinfo->fint < 1750000 ? 0x6 :
+ 0x7;
+
+ l = FLD_MOD(l, f, 4, 1); /* PLL_FREQSEL */
+ } else if (hw->has_selfreqdco) {
+ u32 f = cinfo->clkdco < hw->clkdco_low ? 0x2 : 0x4;
+
+ l = FLD_MOD(l, f, 3, 1); /* PLL_SELFREQDCO */
+ }
+ l = FLD_MOD(l, 1, 13, 13); /* PLL_REFEN */
+ l = FLD_MOD(l, 0, 14, 14); /* PHY_CLKINEN */
+ l = FLD_MOD(l, 0, 16, 16); /* M4_CLOCK_EN */
+ l = FLD_MOD(l, 0, 18, 18); /* M5_CLOCK_EN */
+ l = FLD_MOD(l, 1, 20, 20); /* HSDIVBYPASS */
+ if (hw->has_refsel)
+ l = FLD_MOD(l, 3, 22, 21); /* REFSEL = sysclk */
+ l = FLD_MOD(l, 0, 23, 23); /* M6_CLOCK_EN */
+ l = FLD_MOD(l, 0, 25, 25); /* M7_CLOCK_EN */
+ writel_relaxed(l, base + PLL_CONFIGURATION2);
+
+ writel_relaxed(1, base + PLL_GO); /* PLL_GO */
+
+ if (wait_for_bit_change(base + PLL_GO, 0, 0) != 0) {
+ DSSERR("DSS DPLL GO bit not going down.\n");
+ r = -EIO;
+ goto err;
+ }
+
+ if (wait_for_bit_change(base + PLL_STATUS, 1, 1) != 1) {
+ DSSERR("cannot lock DSS DPLL\n");
+ r = -EIO;
+ goto err;
+ }
+
+ l = readl_relaxed(base + PLL_CONFIGURATION2);
+ l = FLD_MOD(l, 1, 14, 14); /* PHY_CLKINEN */
+ l = FLD_MOD(l, cinfo->mX[0] ? 1 : 0, 16, 16); /* M4_CLOCK_EN */
+ l = FLD_MOD(l, cinfo->mX[1] ? 1 : 0, 18, 18); /* M5_CLOCK_EN */
+ l = FLD_MOD(l, 0, 20, 20); /* HSDIVBYPASS */
+ l = FLD_MOD(l, cinfo->mX[2] ? 1 : 0, 23, 23); /* M6_CLOCK_EN */
+ l = FLD_MOD(l, cinfo->mX[3] ? 1 : 0, 25, 25); /* M7_CLOCK_EN */
+ writel_relaxed(l, base + PLL_CONFIGURATION2);
+
+ r = dss_wait_hsdiv_ack(pll,
+ (cinfo->mX[0] ? BIT(7) : 0) |
+ (cinfo->mX[1] ? BIT(8) : 0) |
+ (cinfo->mX[2] ? BIT(10) : 0) |
+ (cinfo->mX[3] ? BIT(11) : 0));
+ if (r) {
+ DSSERR("failed to enable HSDIV clocks\n");
+ goto err;
+ }
+
+err:
+ return r;
+}
+
+int dss_pll_write_config_type_b(struct dss_pll *pll,
+ const struct dss_pll_clock_info *cinfo)
+{
+ const struct dss_pll_hw *hw = pll->hw;
+ void __iomem *base = pll->base;
+ u32 l;
+
+ l = 0;
+ l = FLD_MOD(l, cinfo->m, 20, 9); /* PLL_REGM */
+ l = FLD_MOD(l, cinfo->n - 1, 8, 1); /* PLL_REGN */
+ writel_relaxed(l, base + PLL_CONFIGURATION1);
+
+ l = readl_relaxed(base + PLL_CONFIGURATION2);
+ l = FLD_MOD(l, 0x0, 12, 12); /* PLL_HIGHFREQ divide by 2 */
+ l = FLD_MOD(l, 0x1, 13, 13); /* PLL_REFEN */
+ l = FLD_MOD(l, 0x0, 14, 14); /* PHY_CLKINEN */
+ if (hw->has_refsel)
+ l = FLD_MOD(l, 0x3, 22, 21); /* REFSEL = SYSCLK */
+
+ /* PLL_SELFREQDCO */
+ if (cinfo->clkdco > hw->clkdco_low)
+ l = FLD_MOD(l, 0x4, 3, 1);
+ else
+ l = FLD_MOD(l, 0x2, 3, 1);
+ writel_relaxed(l, base + PLL_CONFIGURATION2);
+
+ l = readl_relaxed(base + PLL_CONFIGURATION3);
+ l = FLD_MOD(l, cinfo->sd, 17, 10); /* PLL_REGSD */
+ writel_relaxed(l, base + PLL_CONFIGURATION3);
+
+ l = readl_relaxed(base + PLL_CONFIGURATION4);
+ l = FLD_MOD(l, cinfo->mX[0], 24, 18); /* PLL_REGM2 */
+ l = FLD_MOD(l, cinfo->mf, 17, 0); /* PLL_REGM_F */
+ writel_relaxed(l, base + PLL_CONFIGURATION4);
+
+ writel_relaxed(1, base + PLL_GO); /* PLL_GO */
+
+ if (wait_for_bit_change(base + PLL_GO, 0, 0) != 0) {
+ DSSERR("DSS DPLL GO bit not going down.\n");
+ return -EIO;
+ }
+
+ if (wait_for_bit_change(base + PLL_STATUS, 1, 1) != 1) {
+ DSSERR("cannot lock DSS DPLL\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}