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-rw-r--r--arch/x86/kernel/vsmp_64.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
new file mode 100644
index 000000000..796cfaa46
--- /dev/null
+++ b/arch/x86/kernel/vsmp_64.c
@@ -0,0 +1,153 @@
+// 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
+}
+
+static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
+{
+ return hard_smp_processor_id() >> index_msb;
+}
+
+static void vsmp_apic_post_init(void)
+{
+ /* need to update phys_pkg_id */
+ apic->phys_pkg_id = apicid_phys_pkg_id;
+}
+
+void __init vsmp_init(void)
+{
+ detect_vsmp_box();
+ if (!is_vsmp_box())
+ return;
+
+ x86_platform.apic_post_init = vsmp_apic_post_init;
+
+ vsmp_cap_cpus();
+
+ set_vsmp_ctl();
+ return;
+}