linux/arch/x86/kernel/vsmp_64.c
Thomas Gleixner 035fc90a9d x86/apic: Remove unused phys_pkg_id() callback
Now that the core code does not use this monstrosity anymore, it's time to
put it to rest.

The only real purpose was to read the APIC ID on UV and VSMP systems for
the actual evaluation. That's what the core code does now.

For doing the actual shift operation there is truly no APIC callback
required.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.516536121@linutronix.de
2024-02-15 22:07:38 +01:00

140 lines
3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* vSMPowered(tm) systems specific initialization
* Copyright (C) 2005 ScaleMP Inc.
*
* Ravikiran Thirumalai <kiran@scalemp.com>,
* Shai Fultheim <shai@scalemp.com>
* Paravirt ops integration: Glauber de Oliveira Costa <gcosta@redhat.com>,
* Ravikiran Thirumalai <kiran@scalemp.com>
*/
#include <linux/init.h>
#include <linux/pci_ids.h>
#include <linux/pci_regs.h>
#include <linux/smp.h>
#include <linux/irq.h>
#include <asm/apic.h>
#include <asm/pci-direct.h>
#include <asm/io.h>
#include <asm/paravirt.h>
#include <asm/setup.h>
#define TOPOLOGY_REGISTER_OFFSET 0x10
#ifdef CONFIG_PCI
static void __init set_vsmp_ctl(void)
{
void __iomem *address;
unsigned int cap, ctl, cfg;
/* set vSMP magic bits to indicate vSMP capable kernel */
cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
address = early_ioremap(cfg, 8);
cap = readl(address);
ctl = readl(address + 4);
printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n",
cap, ctl);
/* If possible, let the vSMP foundation route the interrupt optimally */
#ifdef CONFIG_SMP
if (cap & ctl & BIT(8)) {
ctl &= ~BIT(8);
#ifdef CONFIG_PROC_FS
/* Don't let users change irq affinity via procfs */
no_irq_affinity = 1;
#endif
}
#endif
writel(ctl, address + 4);
ctl = readl(address + 4);
pr_info("vSMP CTL: control set to:0x%08x\n", ctl);
early_iounmap(address, 8);
}
static int is_vsmp = -1;
static void __init detect_vsmp_box(void)
{
is_vsmp = 0;
if (!early_pci_allowed())
return;
/* Check if we are running on a ScaleMP vSMPowered box */
if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
(PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
is_vsmp = 1;
}
static int is_vsmp_box(void)
{
if (is_vsmp != -1)
return is_vsmp;
else {
WARN_ON_ONCE(1);
return 0;
}
}
#else
static void __init detect_vsmp_box(void)
{
}
static int is_vsmp_box(void)
{
return 0;
}
static void __init set_vsmp_ctl(void)
{
}
#endif
static void __init vsmp_cap_cpus(void)
{
#if !defined(CONFIG_X86_VSMP) && defined(CONFIG_SMP) && defined(CONFIG_PCI)
void __iomem *address;
unsigned int cfg, topology, node_shift, maxcpus;
/*
* CONFIG_X86_VSMP is not configured, so limit the number CPUs to the
* ones present in the first board, unless explicitly overridden by
* setup_max_cpus
*/
if (setup_max_cpus != NR_CPUS)
return;
/* Read the vSMP Foundation topology register */
cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
address = early_ioremap(cfg + TOPOLOGY_REGISTER_OFFSET, 4);
if (WARN_ON(!address))
return;
topology = readl(address);
node_shift = (topology >> 16) & 0x7;
if (!node_shift)
/* The value 0 should be decoded as 8 */
node_shift = 8;
maxcpus = (topology & ((1 << node_shift) - 1)) + 1;
pr_info("vSMP CTL: Capping CPUs to %d (CONFIG_X86_VSMP is unset)\n",
maxcpus);
setup_max_cpus = maxcpus;
early_iounmap(address, 4);
#endif
}
void __init vsmp_init(void)
{
detect_vsmp_box();
if (!is_vsmp_box())
return;
vsmp_cap_cpus();
set_vsmp_ctl();
return;
}