| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/mach-realview/platsmp.c |
| 3 | * |
| 4 | * Copyright (C) 2002 ARM Ltd. |
| 5 | * All Rights Reserved |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/smp.h> |
| 14 | #include <linux/io.h> |
| 15 | |
| 16 | #include <mach/hardware.h> |
| 17 | #include <asm/hardware/gic.h> |
| 18 | #include <asm/mach-types.h> |
| 19 | #include <asm/smp_scu.h> |
| 20 | |
| 21 | #include <mach/board-eb.h> |
| 22 | #include <mach/board-pb11mp.h> |
| 23 | #include <mach/board-pbx.h> |
| 24 | |
| 25 | #include "core.h" |
| 26 | |
| 27 | extern void versatile_secondary_startup(void); |
| 28 | |
| 29 | static void __iomem *scu_base_addr(void) |
| 30 | { |
| 31 | if (machine_is_realview_eb_mp()) |
| 32 | return __io_address(REALVIEW_EB11MP_SCU_BASE); |
| 33 | else if (machine_is_realview_pb11mp()) |
| 34 | return __io_address(REALVIEW_TC11MP_SCU_BASE); |
| 35 | else if (machine_is_realview_pbx() && |
| 36 | (core_tile_pbx11mp() || core_tile_pbxa9mp())) |
| 37 | return __io_address(REALVIEW_PBX_TILE_SCU_BASE); |
| 38 | else |
| 39 | return (void __iomem *)0; |
| 40 | } |
| 41 | |
| 42 | /* |
| 43 | * Initialise the CPU possible map early - this describes the CPUs |
| 44 | * which may be present or become present in the system. |
| 45 | */ |
| 46 | void __init smp_init_cpus(void) |
| 47 | { |
| 48 | void __iomem *scu_base = scu_base_addr(); |
| 49 | unsigned int i, ncores; |
| 50 | |
| 51 | ncores = scu_base ? scu_get_core_count(scu_base) : 1; |
| 52 | |
| 53 | /* sanity check */ |
| 54 | if (ncores > nr_cpu_ids) { |
| 55 | pr_warn("SMP: %u cores greater than maximum (%u), clipping\n", |
| 56 | ncores, nr_cpu_ids); |
| 57 | ncores = nr_cpu_ids; |
| 58 | } |
| 59 | |
| 60 | for (i = 0; i < ncores; i++) |
| 61 | set_cpu_possible(i, true); |
| 62 | |
| 63 | set_smp_cross_call(gic_raise_softirq); |
| 64 | } |
| 65 | |
| 66 | void __init platform_smp_prepare_cpus(unsigned int max_cpus) |
| 67 | { |
| 68 | |
| 69 | scu_enable(scu_base_addr()); |
| 70 | |
| 71 | /* |
| 72 | * Write the address of secondary startup into the |
| 73 | * system-wide flags register. The BootMonitor waits |
| 74 | * until it receives a soft interrupt, and then the |
| 75 | * secondary CPU branches to this address. |
| 76 | */ |
| 77 | __raw_writel(virt_to_phys(versatile_secondary_startup), |
| 78 | __io_address(REALVIEW_SYS_FLAGSSET)); |
| 79 | } |