From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- drivers/of/cpu.c | 210 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 210 insertions(+) create mode 100644 drivers/of/cpu.c (limited to 'drivers/of/cpu.c') diff --git a/drivers/of/cpu.c b/drivers/of/cpu.c new file mode 100644 index 000000000..bd0e918d6 --- /dev/null +++ b/drivers/of/cpu.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +/** + * of_get_cpu_hwid - Get the hardware ID from a CPU device node + * + * @cpun: CPU number(logical index) for which device node is required + * @thread: The local thread number to get the hardware ID for. + * + * Return: The hardware ID for the CPU node or ~0ULL if not found. + */ +u64 of_get_cpu_hwid(struct device_node *cpun, unsigned int thread) +{ + const __be32 *cell; + int ac, len; + + ac = of_n_addr_cells(cpun); + cell = of_get_property(cpun, "reg", &len); + if (!cell || !ac || ((sizeof(*cell) * ac * (thread + 1)) > len)) + return ~0ULL; + + cell += ac * thread; + return of_read_number(cell, ac); +} + +/* + * arch_match_cpu_phys_id - Match the given logical CPU and physical id + * + * @cpu: logical cpu index of a core/thread + * @phys_id: physical identifier of a core/thread + * + * CPU logical to physical index mapping is architecture specific. + * However this __weak function provides a default match of physical + * id to logical cpu index. phys_id provided here is usually values read + * from the device tree which must match the hardware internal registers. + * + * Returns true if the physical identifier and the logical cpu index + * correspond to the same core/thread, false otherwise. + */ +bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id) +{ + return (u32)phys_id == cpu; +} + +/* + * Checks if the given "prop_name" property holds the physical id of the + * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not + * NULL, local thread number within the core is returned in it. + */ +static bool __of_find_n_match_cpu_property(struct device_node *cpun, + const char *prop_name, int cpu, unsigned int *thread) +{ + const __be32 *cell; + int ac, prop_len, tid; + u64 hwid; + + ac = of_n_addr_cells(cpun); + cell = of_get_property(cpun, prop_name, &prop_len); + if (!cell && !ac && arch_match_cpu_phys_id(cpu, 0)) + return true; + if (!cell || !ac || ac > 2) + return false; + prop_len /= sizeof(*cell) * ac; + for (tid = 0; tid < prop_len; tid++) { + hwid = of_read_number(cell, ac); + if (arch_match_cpu_phys_id(cpu, hwid)) { + if (thread) + *thread = tid; + return true; + } + cell += ac; + } + return false; +} + +/* + * arch_find_n_match_cpu_physical_id - See if the given device node is + * for the cpu corresponding to logical cpu 'cpu'. Return true if so, + * else false. If 'thread' is non-NULL, the local thread number within the + * core is returned in it. + */ +bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun, + int cpu, unsigned int *thread) +{ + /* Check for non-standard "ibm,ppc-interrupt-server#s" property + * for thread ids on PowerPC. If it doesn't exist fallback to + * standard "reg" property. + */ + if (IS_ENABLED(CONFIG_PPC) && + __of_find_n_match_cpu_property(cpun, + "ibm,ppc-interrupt-server#s", + cpu, thread)) + return true; + + return __of_find_n_match_cpu_property(cpun, "reg", cpu, thread); +} + +/** + * of_get_cpu_node - Get device node associated with the given logical CPU + * + * @cpu: CPU number(logical index) for which device node is required + * @thread: if not NULL, local thread number within the physical core is + * returned + * + * The main purpose of this function is to retrieve the device node for the + * given logical CPU index. It should be used to initialize the of_node in + * cpu device. Once of_node in cpu device is populated, all the further + * references can use that instead. + * + * CPU logical to physical index mapping is architecture specific and is built + * before booting secondary cores. This function uses arch_match_cpu_phys_id + * which can be overridden by architecture specific implementation. + * + * Return: A node pointer for the logical cpu with refcount incremented, use + * of_node_put() on it when done. Returns NULL if not found. + */ +struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) +{ + struct device_node *cpun; + + for_each_of_cpu_node(cpun) { + if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread)) + return cpun; + } + return NULL; +} +EXPORT_SYMBOL(of_get_cpu_node); + +/** + * of_cpu_device_node_get: Get the CPU device_node for a given logical CPU number + * + * @cpu: The logical CPU number + * + * Return: Pointer to the device_node for CPU with its reference count + * incremented of the given logical CPU number or NULL if the CPU device_node + * is not found. + */ +struct device_node *of_cpu_device_node_get(int cpu) +{ + struct device *cpu_dev; + cpu_dev = get_cpu_device(cpu); + if (!cpu_dev) + return of_get_cpu_node(cpu, NULL); + return of_node_get(cpu_dev->of_node); +} +EXPORT_SYMBOL(of_cpu_device_node_get); + +/** + * of_cpu_node_to_id: Get the logical CPU number for a given device_node + * + * @cpu_node: Pointer to the device_node for CPU. + * + * Return: The logical CPU number of the given CPU device_node or -ENODEV if the + * CPU is not found. + */ +int of_cpu_node_to_id(struct device_node *cpu_node) +{ + int cpu; + bool found = false; + struct device_node *np; + + for_each_possible_cpu(cpu) { + np = of_cpu_device_node_get(cpu); + found = (cpu_node == np); + of_node_put(np); + if (found) + return cpu; + } + + return -ENODEV; +} +EXPORT_SYMBOL(of_cpu_node_to_id); + +/** + * of_get_cpu_state_node - Get CPU's idle state node at the given index + * + * @cpu_node: The device node for the CPU + * @index: The index in the list of the idle states + * + * Two generic methods can be used to describe a CPU's idle states, either via + * a flattened description through the "cpu-idle-states" binding or via the + * hierarchical layout, using the "power-domains" and the "domain-idle-states" + * bindings. This function check for both and returns the idle state node for + * the requested index. + * + * Return: An idle state node if found at @index. The refcount is incremented + * for it, so call of_node_put() on it when done. Returns NULL if not found. + */ +struct device_node *of_get_cpu_state_node(const struct device_node *cpu_node, + int index) +{ + struct of_phandle_args args; + int err; + + err = of_parse_phandle_with_args(cpu_node, "power-domains", + "#power-domain-cells", 0, &args); + if (!err) { + struct device_node *state_node = + of_parse_phandle(args.np, "domain-idle-states", index); + + of_node_put(args.np); + if (state_node) + return state_node; + } + + return of_parse_phandle(cpu_node, "cpu-idle-states", index); +} +EXPORT_SYMBOL(of_get_cpu_state_node); -- cgit v1.3.1