From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- arch/powerpc/sysdev/cpm2.c | 344 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 344 insertions(+) create mode 100644 arch/powerpc/sysdev/cpm2.c (limited to 'arch/powerpc/sysdev/cpm2.c') diff --git a/arch/powerpc/sysdev/cpm2.c b/arch/powerpc/sysdev/cpm2.c new file mode 100644 index 000000000..14cc5ea93 --- /dev/null +++ b/arch/powerpc/sysdev/cpm2.c @@ -0,0 +1,344 @@ +/* + * General Purpose functions for the global management of the + * 8260 Communication Processor Module. + * Copyright (c) 1999-2001 Dan Malek + * Copyright (c) 2000 MontaVista Software, Inc (source@mvista.com) + * 2.3.99 Updates + * + * 2006 (c) MontaVista Software, Inc. + * Vitaly Bordug + * Merged to arch/powerpc from arch/ppc/syslib/cpm2_common.c + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ + +/* + * + * In addition to the individual control of the communication + * channels, there are a few functions that globally affect the + * communication processor. + * + * Buffer descriptors must be allocated from the dual ported memory + * space. The allocator for that is here. When the communication + * process is reset, we reclaim the memory available. There is + * currently no deallocator for this memory. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#include + +cpm_cpm2_t __iomem *cpmp; /* Pointer to comm processor space */ + +/* We allocate this here because it is used almost exclusively for + * the communication processor devices. + */ +cpm2_map_t __iomem *cpm2_immr; +EXPORT_SYMBOL(cpm2_immr); + +#define CPM_MAP_SIZE (0x40000) /* 256k - the PQ3 reserve this amount + of space for CPM as it is larger + than on PQ2 */ + +void __init cpm2_reset(void) +{ +#ifdef CONFIG_PPC_85xx + cpm2_immr = ioremap(get_immrbase() + 0x80000, CPM_MAP_SIZE); +#else + cpm2_immr = ioremap(get_immrbase(), CPM_MAP_SIZE); +#endif + + /* Tell everyone where the comm processor resides. + */ + cpmp = &cpm2_immr->im_cpm; + +#ifndef CONFIG_PPC_EARLY_DEBUG_CPM + /* Reset the CPM. + */ + cpm_command(CPM_CR_RST, 0); +#endif +} + +static DEFINE_SPINLOCK(cmd_lock); + +#define MAX_CR_CMD_LOOPS 10000 + +int cpm_command(u32 command, u8 opcode) +{ + int i, ret; + unsigned long flags; + + spin_lock_irqsave(&cmd_lock, flags); + + ret = 0; + out_be32(&cpmp->cp_cpcr, command | opcode | CPM_CR_FLG); + for (i = 0; i < MAX_CR_CMD_LOOPS; i++) + if ((in_be32(&cpmp->cp_cpcr) & CPM_CR_FLG) == 0) + goto out; + + printk(KERN_ERR "%s(): Not able to issue CPM command\n", __func__); + ret = -EIO; +out: + spin_unlock_irqrestore(&cmd_lock, flags); + return ret; +} +EXPORT_SYMBOL(cpm_command); + +/* Set a baud rate generator. This needs lots of work. There are + * eight BRGs, which can be connected to the CPM channels or output + * as clocks. The BRGs are in two different block of internal + * memory mapped space. + * The baud rate clock is the system clock divided by something. + * It was set up long ago during the initial boot phase and is + * given to us. + * Baud rate clocks are zero-based in the driver code (as that maps + * to port numbers). Documentation uses 1-based numbering. + */ +void __cpm2_setbrg(uint brg, uint rate, uint clk, int div16, int src) +{ + u32 __iomem *bp; + u32 val; + + /* This is good enough to get SMCs running..... + */ + if (brg < 4) { + bp = &cpm2_immr->im_brgc1; + } else { + bp = &cpm2_immr->im_brgc5; + brg -= 4; + } + bp += brg; + /* Round the clock divider to the nearest integer. */ + val = (((clk * 2 / rate) - 1) & ~1) | CPM_BRG_EN | src; + if (div16) + val |= CPM_BRG_DIV16; + + out_be32(bp, val); +} +EXPORT_SYMBOL(__cpm2_setbrg); + +int __init cpm2_clk_setup(enum cpm_clk_target target, int clock, int mode) +{ + int ret = 0; + int shift; + int i, bits = 0; + u32 __iomem *reg; + u32 mask = 7; + + u8 clk_map[][3] = { + {CPM_CLK_FCC1, CPM_BRG5, 0}, + {CPM_CLK_FCC1, CPM_BRG6, 1}, + {CPM_CLK_FCC1, CPM_BRG7, 2}, + {CPM_CLK_FCC1, CPM_BRG8, 3}, + {CPM_CLK_FCC1, CPM_CLK9, 4}, + {CPM_CLK_FCC1, CPM_CLK10, 5}, + {CPM_CLK_FCC1, CPM_CLK11, 6}, + {CPM_CLK_FCC1, CPM_CLK12, 7}, + {CPM_CLK_FCC2, CPM_BRG5, 0}, + {CPM_CLK_FCC2, CPM_BRG6, 1}, + {CPM_CLK_FCC2, CPM_BRG7, 2}, + {CPM_CLK_FCC2, CPM_BRG8, 3}, + {CPM_CLK_FCC2, CPM_CLK13, 4}, + {CPM_CLK_FCC2, CPM_CLK14, 5}, + {CPM_CLK_FCC2, CPM_CLK15, 6}, + {CPM_CLK_FCC2, CPM_CLK16, 7}, + {CPM_CLK_FCC3, CPM_BRG5, 0}, + {CPM_CLK_FCC3, CPM_BRG6, 1}, + {CPM_CLK_FCC3, CPM_BRG7, 2}, + {CPM_CLK_FCC3, CPM_BRG8, 3}, + {CPM_CLK_FCC3, CPM_CLK13, 4}, + {CPM_CLK_FCC3, CPM_CLK14, 5}, + {CPM_CLK_FCC3, CPM_CLK15, 6}, + {CPM_CLK_FCC3, CPM_CLK16, 7}, + {CPM_CLK_SCC1, CPM_BRG1, 0}, + {CPM_CLK_SCC1, CPM_BRG2, 1}, + {CPM_CLK_SCC1, CPM_BRG3, 2}, + {CPM_CLK_SCC1, CPM_BRG4, 3}, + {CPM_CLK_SCC1, CPM_CLK11, 4}, + {CPM_CLK_SCC1, CPM_CLK12, 5}, + {CPM_CLK_SCC1, CPM_CLK3, 6}, + {CPM_CLK_SCC1, CPM_CLK4, 7}, + {CPM_CLK_SCC2, CPM_BRG1, 0}, + {CPM_CLK_SCC2, CPM_BRG2, 1}, + {CPM_CLK_SCC2, CPM_BRG3, 2}, + {CPM_CLK_SCC2, CPM_BRG4, 3}, + {CPM_CLK_SCC2, CPM_CLK11, 4}, + {CPM_CLK_SCC2, CPM_CLK12, 5}, + {CPM_CLK_SCC2, CPM_CLK3, 6}, + {CPM_CLK_SCC2, CPM_CLK4, 7}, + {CPM_CLK_SCC3, CPM_BRG1, 0}, + {CPM_CLK_SCC3, CPM_BRG2, 1}, + {CPM_CLK_SCC3, CPM_BRG3, 2}, + {CPM_CLK_SCC3, CPM_BRG4, 3}, + {CPM_CLK_SCC3, CPM_CLK5, 4}, + {CPM_CLK_SCC3, CPM_CLK6, 5}, + {CPM_CLK_SCC3, CPM_CLK7, 6}, + {CPM_CLK_SCC3, CPM_CLK8, 7}, + {CPM_CLK_SCC4, CPM_BRG1, 0}, + {CPM_CLK_SCC4, CPM_BRG2, 1}, + {CPM_CLK_SCC4, CPM_BRG3, 2}, + {CPM_CLK_SCC4, CPM_BRG4, 3}, + {CPM_CLK_SCC4, CPM_CLK5, 4}, + {CPM_CLK_SCC4, CPM_CLK6, 5}, + {CPM_CLK_SCC4, CPM_CLK7, 6}, + {CPM_CLK_SCC4, CPM_CLK8, 7}, + }; + + switch (target) { + case CPM_CLK_SCC1: + reg = &cpm2_immr->im_cpmux.cmx_scr; + shift = 24; + break; + case CPM_CLK_SCC2: + reg = &cpm2_immr->im_cpmux.cmx_scr; + shift = 16; + break; + case CPM_CLK_SCC3: + reg = &cpm2_immr->im_cpmux.cmx_scr; + shift = 8; + break; + case CPM_CLK_SCC4: + reg = &cpm2_immr->im_cpmux.cmx_scr; + shift = 0; + break; + case CPM_CLK_FCC1: + reg = &cpm2_immr->im_cpmux.cmx_fcr; + shift = 24; + break; + case CPM_CLK_FCC2: + reg = &cpm2_immr->im_cpmux.cmx_fcr; + shift = 16; + break; + case CPM_CLK_FCC3: + reg = &cpm2_immr->im_cpmux.cmx_fcr; + shift = 8; + break; + default: + printk(KERN_ERR "cpm2_clock_setup: invalid clock target\n"); + return -EINVAL; + } + + for (i = 0; i < ARRAY_SIZE(clk_map); i++) { + if (clk_map[i][0] == target && clk_map[i][1] == clock) { + bits = clk_map[i][2]; + break; + } + } + if (i == ARRAY_SIZE(clk_map)) + ret = -EINVAL; + + bits <<= shift; + mask <<= shift; + + if (mode == CPM_CLK_RTX) { + bits |= bits << 3; + mask |= mask << 3; + } else if (mode == CPM_CLK_RX) { + bits <<= 3; + mask <<= 3; + } + + out_be32(reg, (in_be32(reg) & ~mask) | bits); + + return ret; +} + +int __init cpm2_smc_clk_setup(enum cpm_clk_target target, int clock) +{ + int ret = 0; + int shift; + int i, bits = 0; + u8 __iomem *reg; + u8 mask = 3; + + u8 clk_map[][3] = { + {CPM_CLK_SMC1, CPM_BRG1, 0}, + {CPM_CLK_SMC1, CPM_BRG7, 1}, + {CPM_CLK_SMC1, CPM_CLK7, 2}, + {CPM_CLK_SMC1, CPM_CLK9, 3}, + {CPM_CLK_SMC2, CPM_BRG2, 0}, + {CPM_CLK_SMC2, CPM_BRG8, 1}, + {CPM_CLK_SMC2, CPM_CLK4, 2}, + {CPM_CLK_SMC2, CPM_CLK15, 3}, + }; + + switch (target) { + case CPM_CLK_SMC1: + reg = &cpm2_immr->im_cpmux.cmx_smr; + mask = 3; + shift = 4; + break; + case CPM_CLK_SMC2: + reg = &cpm2_immr->im_cpmux.cmx_smr; + mask = 3; + shift = 0; + break; + default: + printk(KERN_ERR "cpm2_smc_clock_setup: invalid clock target\n"); + return -EINVAL; + } + + for (i = 0; i < ARRAY_SIZE(clk_map); i++) { + if (clk_map[i][0] == target && clk_map[i][1] == clock) { + bits = clk_map[i][2]; + break; + } + } + if (i == ARRAY_SIZE(clk_map)) + ret = -EINVAL; + + bits <<= shift; + mask <<= shift; + + out_8(reg, (in_8(reg) & ~mask) | bits); + + return ret; +} + +struct cpm2_ioports { + u32 dir, par, sor, odr, dat; + u32 res[3]; +}; + +void __init cpm2_set_pin(int port, int pin, int flags) +{ + struct cpm2_ioports __iomem *iop = + (struct cpm2_ioports __iomem *)&cpm2_immr->im_ioport; + + pin = 1 << (31 - pin); + + if (flags & CPM_PIN_OUTPUT) + setbits32(&iop[port].dir, pin); + else + clrbits32(&iop[port].dir, pin); + + if (!(flags & CPM_PIN_GPIO)) + setbits32(&iop[port].par, pin); + else + clrbits32(&iop[port].par, pin); + + if (flags & CPM_PIN_SECONDARY) + setbits32(&iop[port].sor, pin); + else + clrbits32(&iop[port].sor, pin); + + if (flags & CPM_PIN_OPENDRAIN) + setbits32(&iop[port].odr, pin); + else + clrbits32(&iop[port].odr, pin); +} -- cgit v1.3.1