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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/clk/bcm/clk-raspberrypi.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/clk/bcm/clk-raspberrypi.c')
-rw-r--r--drivers/clk/bcm/clk-raspberrypi.c470
1 files changed, 470 insertions, 0 deletions
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
new file mode 100644
index 000000000..ce2f93479
--- /dev/null
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -0,0 +1,470 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Raspberry Pi driver for firmware controlled clocks
+ *
+ * Even though clk-bcm2835 provides an interface to the hardware registers for
+ * the system clocks we've had to factor out 'pllb' as the firmware 'owns' it.
+ * We're not allowed to change it directly as we might race with the
+ * over-temperature and under-voltage protections provided by the firmware.
+ *
+ * Copyright (C) 2019 Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+ */
+
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
+static char *rpi_firmware_clk_names[] = {
+ [RPI_FIRMWARE_EMMC_CLK_ID] = "emmc",
+ [RPI_FIRMWARE_UART_CLK_ID] = "uart",
+ [RPI_FIRMWARE_ARM_CLK_ID] = "arm",
+ [RPI_FIRMWARE_CORE_CLK_ID] = "core",
+ [RPI_FIRMWARE_V3D_CLK_ID] = "v3d",
+ [RPI_FIRMWARE_H264_CLK_ID] = "h264",
+ [RPI_FIRMWARE_ISP_CLK_ID] = "isp",
+ [RPI_FIRMWARE_SDRAM_CLK_ID] = "sdram",
+ [RPI_FIRMWARE_PIXEL_CLK_ID] = "pixel",
+ [RPI_FIRMWARE_PWM_CLK_ID] = "pwm",
+ [RPI_FIRMWARE_HEVC_CLK_ID] = "hevc",
+ [RPI_FIRMWARE_EMMC2_CLK_ID] = "emmc2",
+ [RPI_FIRMWARE_M2MC_CLK_ID] = "m2mc",
+ [RPI_FIRMWARE_PIXEL_BVB_CLK_ID] = "pixel-bvb",
+ [RPI_FIRMWARE_VEC_CLK_ID] = "vec",
+};
+
+#define RPI_FIRMWARE_STATE_ENABLE_BIT BIT(0)
+#define RPI_FIRMWARE_STATE_WAIT_BIT BIT(1)
+
+struct raspberrypi_clk_variant;
+
+struct raspberrypi_clk {
+ struct device *dev;
+ struct rpi_firmware *firmware;
+ struct platform_device *cpufreq;
+};
+
+struct raspberrypi_clk_data {
+ struct clk_hw hw;
+
+ unsigned int id;
+ struct raspberrypi_clk_variant *variant;
+
+ struct raspberrypi_clk *rpi;
+};
+
+struct raspberrypi_clk_variant {
+ bool export;
+ char *clkdev;
+ unsigned long min_rate;
+ bool minimize;
+};
+
+static struct raspberrypi_clk_variant
+raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
+ [RPI_FIRMWARE_ARM_CLK_ID] = {
+ .export = true,
+ .clkdev = "cpu0",
+ },
+ [RPI_FIRMWARE_CORE_CLK_ID] = {
+ .export = true,
+
+ /*
+ * The clock is shared between the HVS and the CSI
+ * controllers, on the BCM2711 and will change depending
+ * on the pixels composited on the HVS and the capture
+ * resolution on Unicam.
+ *
+ * Since the rate can get quite large, and we need to
+ * coordinate between both driver instances, let's
+ * always use the minimum the drivers will let us.
+ */
+ .minimize = true,
+ },
+ [RPI_FIRMWARE_M2MC_CLK_ID] = {
+ .export = true,
+
+ /*
+ * If we boot without any cable connected to any of the
+ * HDMI connector, the firmware will skip the HSM
+ * initialization and leave it with a rate of 0,
+ * resulting in a bus lockup when we're accessing the
+ * registers even if it's enabled.
+ *
+ * Let's put a sensible default so that we don't end up
+ * in this situation.
+ */
+ .min_rate = 120000000,
+
+ /*
+ * The clock is shared between the two HDMI controllers
+ * on the BCM2711 and will change depending on the
+ * resolution output on each. Since the rate can get
+ * quite large, and we need to coordinate between both
+ * driver instances, let's always use the minimum the
+ * drivers will let us.
+ */
+ .minimize = true,
+ },
+ [RPI_FIRMWARE_V3D_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_PIXEL_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_HEVC_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_PIXEL_BVB_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_VEC_CLK_ID] = {
+ .export = true,
+ },
+};
+
+/*
+ * Structure of the message passed to Raspberry Pi's firmware in order to
+ * change clock rates. The 'disable_turbo' option is only available to the ARM
+ * clock (pllb) which we enable by default as turbo mode will alter multiple
+ * clocks at once.
+ *
+ * Even though we're able to access the clock registers directly we're bound to
+ * use the firmware interface as the firmware ultimately takes care of
+ * mitigating overheating/undervoltage situations and we would be changing
+ * frequencies behind his back.
+ *
+ * For more information on the firmware interface check:
+ * https://github.com/raspberrypi/firmware/wiki/Mailbox-property-interface
+ */
+struct raspberrypi_firmware_prop {
+ __le32 id;
+ __le32 val;
+ __le32 disable_turbo;
+} __packed;
+
+static int raspberrypi_clock_property(struct rpi_firmware *firmware,
+ const struct raspberrypi_clk_data *data,
+ u32 tag, u32 *val)
+{
+ struct raspberrypi_firmware_prop msg = {
+ .id = cpu_to_le32(data->id),
+ .val = cpu_to_le32(*val),
+ .disable_turbo = cpu_to_le32(1),
+ };
+ int ret;
+
+ ret = rpi_firmware_property(firmware, tag, &msg, sizeof(msg));
+ if (ret)
+ return ret;
+
+ *val = le32_to_cpu(msg.val);
+
+ return 0;
+}
+
+static int raspberrypi_fw_is_prepared(struct clk_hw *hw)
+{
+ struct raspberrypi_clk_data *data =
+ container_of(hw, struct raspberrypi_clk_data, hw);
+ struct raspberrypi_clk *rpi = data->rpi;
+ u32 val = 0;
+ int ret;
+
+ ret = raspberrypi_clock_property(rpi->firmware, data,
+ RPI_FIRMWARE_GET_CLOCK_STATE, &val);
+ if (ret)
+ return 0;
+
+ return !!(val & RPI_FIRMWARE_STATE_ENABLE_BIT);
+}
+
+
+static unsigned long raspberrypi_fw_get_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct raspberrypi_clk_data *data =
+ container_of(hw, struct raspberrypi_clk_data, hw);
+ struct raspberrypi_clk *rpi = data->rpi;
+ u32 val = 0;
+ int ret;
+
+ ret = raspberrypi_clock_property(rpi->firmware, data,
+ RPI_FIRMWARE_GET_CLOCK_RATE, &val);
+ if (ret)
+ return 0;
+
+ return val;
+}
+
+static int raspberrypi_fw_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct raspberrypi_clk_data *data =
+ container_of(hw, struct raspberrypi_clk_data, hw);
+ struct raspberrypi_clk *rpi = data->rpi;
+ u32 _rate = rate;
+ int ret;
+
+ ret = raspberrypi_clock_property(rpi->firmware, data,
+ RPI_FIRMWARE_SET_CLOCK_RATE, &_rate);
+ if (ret)
+ dev_err_ratelimited(rpi->dev, "Failed to change %s frequency: %d\n",
+ clk_hw_get_name(hw), ret);
+
+ return ret;
+}
+
+static int raspberrypi_fw_dumb_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct raspberrypi_clk_data *data =
+ container_of(hw, struct raspberrypi_clk_data, hw);
+ struct raspberrypi_clk_variant *variant = data->variant;
+
+ /*
+ * The firmware will do the rounding but that isn't part of
+ * the interface with the firmware, so we just do our best
+ * here.
+ */
+
+ req->rate = clamp(req->rate, req->min_rate, req->max_rate);
+
+ /*
+ * We want to aggressively reduce the clock rate here, so let's
+ * just ignore the requested rate and return the bare minimum
+ * rate we can get away with.
+ */
+ if (variant->minimize && req->min_rate > 0)
+ req->rate = req->min_rate;
+
+ return 0;
+}
+
+static const struct clk_ops raspberrypi_firmware_clk_ops = {
+ .is_prepared = raspberrypi_fw_is_prepared,
+ .recalc_rate = raspberrypi_fw_get_rate,
+ .determine_rate = raspberrypi_fw_dumb_determine_rate,
+ .set_rate = raspberrypi_fw_set_rate,
+};
+
+static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
+ unsigned int parent,
+ unsigned int id,
+ struct raspberrypi_clk_variant *variant)
+{
+ struct raspberrypi_clk_data *data;
+ struct clk_init_data init = {};
+ u32 min_rate, max_rate;
+ int ret;
+
+ data = devm_kzalloc(rpi->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return ERR_PTR(-ENOMEM);
+ data->rpi = rpi;
+ data->id = id;
+ data->variant = variant;
+
+ init.name = devm_kasprintf(rpi->dev, GFP_KERNEL,
+ "fw-clk-%s",
+ rpi_firmware_clk_names[id]);
+ init.ops = &raspberrypi_firmware_clk_ops;
+ init.flags = CLK_GET_RATE_NOCACHE;
+
+ data->hw.init = &init;
+
+ ret = raspberrypi_clock_property(rpi->firmware, data,
+ RPI_FIRMWARE_GET_MIN_CLOCK_RATE,
+ &min_rate);
+ if (ret) {
+ dev_err(rpi->dev, "Failed to get clock %d min freq: %d\n",
+ id, ret);
+ return ERR_PTR(ret);
+ }
+
+ ret = raspberrypi_clock_property(rpi->firmware, data,
+ RPI_FIRMWARE_GET_MAX_CLOCK_RATE,
+ &max_rate);
+ if (ret) {
+ dev_err(rpi->dev, "Failed to get clock %d max freq: %d\n",
+ id, ret);
+ return ERR_PTR(ret);
+ }
+
+ ret = devm_clk_hw_register(rpi->dev, &data->hw);
+ if (ret)
+ return ERR_PTR(ret);
+
+ clk_hw_set_rate_range(&data->hw, min_rate, max_rate);
+
+ if (variant->clkdev) {
+ ret = devm_clk_hw_register_clkdev(rpi->dev, &data->hw,
+ NULL, variant->clkdev);
+ if (ret) {
+ dev_err(rpi->dev, "Failed to initialize clkdev\n");
+ return ERR_PTR(ret);
+ }
+ }
+
+ if (variant->min_rate) {
+ unsigned long rate;
+
+ clk_hw_set_rate_range(&data->hw, variant->min_rate, max_rate);
+
+ rate = raspberrypi_fw_get_rate(&data->hw, 0);
+ if (rate < variant->min_rate) {
+ ret = raspberrypi_fw_set_rate(&data->hw, variant->min_rate, 0);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+ }
+
+ return &data->hw;
+}
+
+struct rpi_firmware_get_clocks_response {
+ u32 parent;
+ u32 id;
+};
+
+static int raspberrypi_discover_clocks(struct raspberrypi_clk *rpi,
+ struct clk_hw_onecell_data *data)
+{
+ struct rpi_firmware_get_clocks_response *clks;
+ int ret;
+
+ /*
+ * The firmware doesn't guarantee that the last element of
+ * RPI_FIRMWARE_GET_CLOCKS is zeroed. So allocate an additional
+ * zero element as sentinel.
+ */
+ clks = devm_kcalloc(rpi->dev,
+ RPI_FIRMWARE_NUM_CLK_ID + 1, sizeof(*clks),
+ GFP_KERNEL);
+ if (!clks)
+ return -ENOMEM;
+
+ ret = rpi_firmware_property(rpi->firmware, RPI_FIRMWARE_GET_CLOCKS,
+ clks,
+ sizeof(*clks) * RPI_FIRMWARE_NUM_CLK_ID);
+ if (ret)
+ return ret;
+
+ while (clks->id) {
+ struct raspberrypi_clk_variant *variant;
+
+ if (clks->id > RPI_FIRMWARE_NUM_CLK_ID) {
+ dev_err(rpi->dev, "Unknown clock id: %u (max: %u)\n",
+ clks->id, RPI_FIRMWARE_NUM_CLK_ID);
+ return -EINVAL;
+ }
+
+ variant = &raspberrypi_clk_variants[clks->id];
+ if (variant->export) {
+ struct clk_hw *hw;
+
+ hw = raspberrypi_clk_register(rpi, clks->parent,
+ clks->id, variant);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ data->hws[clks->id] = hw;
+ data->num = clks->id + 1;
+ }
+
+ clks++;
+ }
+
+ return 0;
+}
+
+static int raspberrypi_clk_probe(struct platform_device *pdev)
+{
+ struct clk_hw_onecell_data *clk_data;
+ struct device_node *firmware_node;
+ struct device *dev = &pdev->dev;
+ struct rpi_firmware *firmware;
+ struct raspberrypi_clk *rpi;
+ int ret;
+
+ /*
+ * We can be probed either through the an old-fashioned
+ * platform device registration or through a DT node that is a
+ * child of the firmware node. Handle both cases.
+ */
+ if (dev->of_node)
+ firmware_node = of_get_parent(dev->of_node);
+ else
+ firmware_node = of_find_compatible_node(NULL, NULL,
+ "raspberrypi,bcm2835-firmware");
+ if (!firmware_node) {
+ dev_err(dev, "Missing firmware node\n");
+ return -ENOENT;
+ }
+
+ firmware = devm_rpi_firmware_get(&pdev->dev, firmware_node);
+ of_node_put(firmware_node);
+ if (!firmware)
+ return -EPROBE_DEFER;
+
+ rpi = devm_kzalloc(dev, sizeof(*rpi), GFP_KERNEL);
+ if (!rpi)
+ return -ENOMEM;
+
+ rpi->dev = dev;
+ rpi->firmware = firmware;
+ platform_set_drvdata(pdev, rpi);
+
+ clk_data = devm_kzalloc(dev, struct_size(clk_data, hws,
+ RPI_FIRMWARE_NUM_CLK_ID),
+ GFP_KERNEL);
+ if (!clk_data)
+ return -ENOMEM;
+
+ ret = raspberrypi_discover_clocks(rpi, clk_data);
+ if (ret)
+ return ret;
+
+ ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+ clk_data);
+ if (ret)
+ return ret;
+
+ rpi->cpufreq = platform_device_register_data(dev, "raspberrypi-cpufreq",
+ -1, NULL, 0);
+
+ return 0;
+}
+
+static int raspberrypi_clk_remove(struct platform_device *pdev)
+{
+ struct raspberrypi_clk *rpi = platform_get_drvdata(pdev);
+
+ platform_device_unregister(rpi->cpufreq);
+
+ return 0;
+}
+
+static const struct of_device_id raspberrypi_clk_match[] = {
+ { .compatible = "raspberrypi,firmware-clocks" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, raspberrypi_clk_match);
+
+static struct platform_driver raspberrypi_clk_driver = {
+ .driver = {
+ .name = "raspberrypi-clk",
+ .of_match_table = raspberrypi_clk_match,
+ },
+ .probe = raspberrypi_clk_probe,
+ .remove = raspberrypi_clk_remove,
+};
+module_platform_driver(raspberrypi_clk_driver);
+
+MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de>");
+MODULE_DESCRIPTION("Raspberry Pi firmware clock driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:raspberrypi-clk");