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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/x86/kernel/cpu/cyrix.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'arch/x86/kernel/cpu/cyrix.c')
-rw-r--r--arch/x86/kernel/cpu/cyrix.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
new file mode 100644
index 000000000..9651275ae
--- /dev/null
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -0,0 +1,467 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/isa-dma.h>
+#include <linux/pci.h>
+#include <asm/dma.h>
+#include <linux/io.h>
+#include <asm/processor-cyrix.h>
+#include <asm/processor-flags.h>
+#include <linux/timer.h>
+#include <asm/pci-direct.h>
+#include <asm/tsc.h>
+#include <asm/cpufeature.h>
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+
+#include "cpu.h"
+
+/*
+ * Read NSC/Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
+ */
+static void __do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+{
+ unsigned char ccr2, ccr3;
+
+ /* we test for DEVID by checking whether CCR3 is writable */
+ ccr3 = getCx86(CX86_CCR3);
+ setCx86(CX86_CCR3, ccr3 ^ 0x80);
+ getCx86(0xc0); /* dummy to change bus */
+
+ if (getCx86(CX86_CCR3) == ccr3) { /* no DEVID regs. */
+ ccr2 = getCx86(CX86_CCR2);
+ setCx86(CX86_CCR2, ccr2 ^ 0x04);
+ getCx86(0xc0); /* dummy */
+
+ if (getCx86(CX86_CCR2) == ccr2) /* old Cx486SLC/DLC */
+ *dir0 = 0xfd;
+ else { /* Cx486S A step */
+ setCx86(CX86_CCR2, ccr2);
+ *dir0 = 0xfe;
+ }
+ } else {
+ setCx86(CX86_CCR3, ccr3); /* restore CCR3 */
+
+ /* read DIR0 and DIR1 CPU registers */
+ *dir0 = getCx86(CX86_DIR0);
+ *dir1 = getCx86(CX86_DIR1);
+ }
+}
+
+static void do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __do_cyrix_devid(dir0, dir1);
+ local_irq_restore(flags);
+}
+/*
+ * Cx86_dir0_msb is a HACK needed by check_cx686_cpuid/slop in bugs.h in
+ * order to identify the Cyrix CPU model after we're out of setup.c
+ *
+ * Actually since bugs.h doesn't even reference this perhaps someone should
+ * fix the documentation ???
+ */
+static unsigned char Cx86_dir0_msb = 0;
+
+static const char Cx86_model[][9] = {
+ "Cx486", "Cx486", "5x86 ", "6x86", "MediaGX ", "6x86MX ",
+ "M II ", "Unknown"
+};
+static const char Cx486_name[][5] = {
+ "SLC", "DLC", "SLC2", "DLC2", "SRx", "DRx",
+ "SRx2", "DRx2"
+};
+static const char Cx486S_name[][4] = {
+ "S", "S2", "Se", "S2e"
+};
+static const char Cx486D_name[][4] = {
+ "DX", "DX2", "?", "?", "?", "DX4"
+};
+static char Cx86_cb[] = "?.5x Core/Bus Clock";
+static const char cyrix_model_mult1[] = "12??43";
+static const char cyrix_model_mult2[] = "12233445";
+
+/*
+ * Reset the slow-loop (SLOP) bit on the 686(L) which is set by some old
+ * BIOSes for compatibility with DOS games. This makes the udelay loop
+ * work correctly, and improves performance.
+ *
+ * FIXME: our newer udelay uses the tsc. We don't need to frob with SLOP
+ */
+
+static void check_cx686_slop(struct cpuinfo_x86 *c)
+{
+ unsigned long flags;
+
+ if (Cx86_dir0_msb == 3) {
+ unsigned char ccr3, ccr5;
+
+ local_irq_save(flags);
+ ccr3 = getCx86(CX86_CCR3);
+ setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+ ccr5 = getCx86(CX86_CCR5);
+ if (ccr5 & 2)
+ setCx86(CX86_CCR5, ccr5 & 0xfd); /* reset SLOP */
+ setCx86(CX86_CCR3, ccr3); /* disable MAPEN */
+ local_irq_restore(flags);
+
+ if (ccr5 & 2) { /* possible wrong calibration done */
+ pr_info("Recalibrating delay loop with SLOP bit reset\n");
+ calibrate_delay();
+ c->loops_per_jiffy = loops_per_jiffy;
+ }
+ }
+}
+
+
+static void set_cx86_reorder(void)
+{
+ u8 ccr3;
+
+ pr_info("Enable Memory access reorder on Cyrix/NSC processor.\n");
+ ccr3 = getCx86(CX86_CCR3);
+ setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+
+ /* Load/Store Serialize to mem access disable (=reorder it) */
+ setCx86(CX86_PCR0, getCx86(CX86_PCR0) & ~0x80);
+ /* set load/store serialize from 1GB to 4GB */
+ ccr3 |= 0xe0;
+ setCx86(CX86_CCR3, ccr3);
+}
+
+static void set_cx86_memwb(void)
+{
+ pr_info("Enable Memory-Write-back mode on Cyrix/NSC processor.\n");
+
+ /* CCR2 bit 2: unlock NW bit */
+ setCx86(CX86_CCR2, getCx86(CX86_CCR2) & ~0x04);
+ /* set 'Not Write-through' */
+ write_cr0(read_cr0() | X86_CR0_NW);
+ /* CCR2 bit 2: lock NW bit and set WT1 */
+ setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x14);
+}
+
+/*
+ * Configure later MediaGX and/or Geode processor.
+ */
+
+static void geode_configure(void)
+{
+ unsigned long flags;
+ u8 ccr3;
+ local_irq_save(flags);
+
+ /* Suspend on halt power saving and enable #SUSP pin */
+ setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
+
+ ccr3 = getCx86(CX86_CCR3);
+ setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+
+
+ /* FPU fast, DTE cache, Mem bypass */
+ setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x38);
+ setCx86(CX86_CCR3, ccr3); /* disable MAPEN */
+
+ set_cx86_memwb();
+ set_cx86_reorder();
+
+ local_irq_restore(flags);
+}
+
+static void early_init_cyrix(struct cpuinfo_x86 *c)
+{
+ unsigned char dir0, dir0_msn, dir1 = 0;
+
+ __do_cyrix_devid(&dir0, &dir1);
+ dir0_msn = dir0 >> 4; /* identifies CPU "family" */
+
+ switch (dir0_msn) {
+ case 3: /* 6x86/6x86L */
+ /* Emulate MTRRs using Cyrix's ARRs. */
+ set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+ break;
+ case 5: /* 6x86MX/M II */
+ /* Emulate MTRRs using Cyrix's ARRs. */
+ set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+ break;
+ }
+}
+
+static void init_cyrix(struct cpuinfo_x86 *c)
+{
+ unsigned char dir0, dir0_msn, dir0_lsn, dir1 = 0;
+ char *buf = c->x86_model_id;
+ const char *p = NULL;
+
+ /*
+ * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+ * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+ */
+ clear_cpu_cap(c, 0*32+31);
+
+ /* Cyrix used bit 24 in extended (AMD) CPUID for Cyrix MMX extensions */
+ if (test_cpu_cap(c, 1*32+24)) {
+ clear_cpu_cap(c, 1*32+24);
+ set_cpu_cap(c, X86_FEATURE_CXMMX);
+ }
+
+ do_cyrix_devid(&dir0, &dir1);
+
+ check_cx686_slop(c);
+
+ Cx86_dir0_msb = dir0_msn = dir0 >> 4; /* identifies CPU "family" */
+ dir0_lsn = dir0 & 0xf; /* model or clock multiplier */
+
+ /* common case step number/rev -- exceptions handled below */
+ c->x86_model = (dir1 >> 4) + 1;
+ c->x86_stepping = dir1 & 0xf;
+
+ /* Now cook; the original recipe is by Channing Corn, from Cyrix.
+ * We do the same thing for each generation: we work out
+ * the model, multiplier and stepping. Black magic included,
+ * to make the silicon step/rev numbers match the printed ones.
+ */
+
+ switch (dir0_msn) {
+ unsigned char tmp;
+
+ case 0: /* Cx486SLC/DLC/SRx/DRx */
+ p = Cx486_name[dir0_lsn & 7];
+ break;
+
+ case 1: /* Cx486S/DX/DX2/DX4 */
+ p = (dir0_lsn & 8) ? Cx486D_name[dir0_lsn & 5]
+ : Cx486S_name[dir0_lsn & 3];
+ break;
+
+ case 2: /* 5x86 */
+ Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
+ p = Cx86_cb+2;
+ break;
+
+ case 3: /* 6x86/6x86L */
+ Cx86_cb[1] = ' ';
+ Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
+ if (dir1 > 0x21) { /* 686L */
+ Cx86_cb[0] = 'L';
+ p = Cx86_cb;
+ (c->x86_model)++;
+ } else /* 686 */
+ p = Cx86_cb+1;
+ /* Emulate MTRRs using Cyrix's ARRs. */
+ set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+ /* 6x86's contain this bug */
+ set_cpu_bug(c, X86_BUG_COMA);
+ break;
+
+ case 4: /* MediaGX/GXm or Geode GXM/GXLV/GX1 */
+ case 11: /* GX1 with inverted Device ID */
+#ifdef CONFIG_PCI
+ {
+ u32 vendor, device;
+ /*
+ * It isn't really a PCI quirk directly, but the cure is the
+ * same. The MediaGX has deep magic SMM stuff that handles the
+ * SB emulation. It throws away the fifo on disable_dma() which
+ * is wrong and ruins the audio.
+ *
+ * Bug2: VSA1 has a wrap bug so that using maximum sized DMA
+ * causes bad things. According to NatSemi VSA2 has another
+ * bug to do with 'hlt'. I've not seen any boards using VSA2
+ * and X doesn't seem to support it either so who cares 8).
+ * VSA1 we work around however.
+ */
+
+ pr_info("Working around Cyrix MediaGX virtual DMA bugs.\n");
+ isa_dma_bridge_buggy = 2;
+
+ /* We do this before the PCI layer is running. However we
+ are safe here as we know the bridge must be a Cyrix
+ companion and must be present */
+ vendor = read_pci_config_16(0, 0, 0x12, PCI_VENDOR_ID);
+ device = read_pci_config_16(0, 0, 0x12, PCI_DEVICE_ID);
+
+ /*
+ * The 5510/5520 companion chips have a funky PIT.
+ */
+ if (vendor == PCI_VENDOR_ID_CYRIX &&
+ (device == PCI_DEVICE_ID_CYRIX_5510 ||
+ device == PCI_DEVICE_ID_CYRIX_5520))
+ mark_tsc_unstable("cyrix 5510/5520 detected");
+ }
+#endif
+ c->x86_cache_size = 16; /* Yep 16K integrated cache that's it */
+
+ /* GXm supports extended cpuid levels 'ala' AMD */
+ if (c->cpuid_level == 2) {
+ /* Enable cxMMX extensions (GX1 Datasheet 54) */
+ setCx86(CX86_CCR7, getCx86(CX86_CCR7) | 1);
+
+ /*
+ * GXm : 0x30 ... 0x5f GXm datasheet 51
+ * GXlv: 0x6x GXlv datasheet 54
+ * ? : 0x7x
+ * GX1 : 0x8x GX1 datasheet 56
+ */
+ if ((0x30 <= dir1 && dir1 <= 0x6f) ||
+ (0x80 <= dir1 && dir1 <= 0x8f))
+ geode_configure();
+ return;
+ } else { /* MediaGX */
+ Cx86_cb[2] = (dir0_lsn & 1) ? '3' : '4';
+ p = Cx86_cb+2;
+ c->x86_model = (dir1 & 0x20) ? 1 : 2;
+ }
+ break;
+
+ case 5: /* 6x86MX/M II */
+ if (dir1 > 7) {
+ dir0_msn++; /* M II */
+ /* Enable MMX extensions (App note 108) */
+ setCx86(CX86_CCR7, getCx86(CX86_CCR7)|1);
+ } else {
+ /* A 6x86MX - it has the bug. */
+ set_cpu_bug(c, X86_BUG_COMA);
+ }
+ tmp = (!(dir0_lsn & 7) || dir0_lsn & 1) ? 2 : 0;
+ Cx86_cb[tmp] = cyrix_model_mult2[dir0_lsn & 7];
+ p = Cx86_cb+tmp;
+ if (((dir1 & 0x0f) > 4) || ((dir1 & 0xf0) == 0x20))
+ (c->x86_model)++;
+ /* Emulate MTRRs using Cyrix's ARRs. */
+ set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+ break;
+
+ case 0xf: /* Cyrix 486 without DEVID registers */
+ switch (dir0_lsn) {
+ case 0xd: /* either a 486SLC or DLC w/o DEVID */
+ dir0_msn = 0;
+ p = Cx486_name[!!boot_cpu_has(X86_FEATURE_FPU)];
+ break;
+
+ case 0xe: /* a 486S A step */
+ dir0_msn = 0;
+ p = Cx486S_name[0];
+ break;
+ }
+ break;
+
+ default: /* unknown (shouldn't happen, we know everyone ;-) */
+ dir0_msn = 7;
+ break;
+ }
+ strcpy(buf, Cx86_model[dir0_msn & 7]);
+ if (p)
+ strcat(buf, p);
+ return;
+}
+
+/*
+ * Handle National Semiconductor branded processors
+ */
+static void init_nsc(struct cpuinfo_x86 *c)
+{
+ /*
+ * There may be GX1 processors in the wild that are branded
+ * NSC and not Cyrix.
+ *
+ * This function only handles the GX processor, and kicks every
+ * thing else to the Cyrix init function above - that should
+ * cover any processors that might have been branded differently
+ * after NSC acquired Cyrix.
+ *
+ * If this breaks your GX1 horribly, please e-mail
+ * info-linux@ldcmail.amd.com to tell us.
+ */
+
+ /* Handle the GX (Formally known as the GX2) */
+
+ if (c->x86 == 5 && c->x86_model == 5)
+ cpu_detect_cache_sizes(c);
+ else
+ init_cyrix(c);
+}
+
+/*
+ * Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
+ * by the fact that they preserve the flags across the division of 5/2.
+ * PII and PPro exhibit this behavior too, but they have cpuid available.
+ */
+
+/*
+ * Perform the Cyrix 5/2 test. A Cyrix won't change
+ * the flags, while other 486 chips will.
+ */
+static inline int test_cyrix_52div(void)
+{
+ unsigned int test;
+
+ __asm__ __volatile__(
+ "sahf\n\t" /* clear flags (%eax = 0x0005) */
+ "div %b2\n\t" /* divide 5 by 2 */
+ "lahf" /* store flags into %ah */
+ : "=a" (test)
+ : "0" (5), "q" (2)
+ : "cc");
+
+ /* AH is 0x02 on Cyrix after the divide.. */
+ return (unsigned char) (test >> 8) == 0x02;
+}
+
+static void cyrix_identify(struct cpuinfo_x86 *c)
+{
+ /* Detect Cyrix with disabled CPUID */
+ if (c->x86 == 4 && test_cyrix_52div()) {
+ unsigned char dir0, dir1;
+
+ strcpy(c->x86_vendor_id, "CyrixInstead");
+ c->x86_vendor = X86_VENDOR_CYRIX;
+
+ /* Actually enable cpuid on the older cyrix */
+
+ /* Retrieve CPU revisions */
+
+ do_cyrix_devid(&dir0, &dir1);
+
+ dir0 >>= 4;
+
+ /* Check it is an affected model */
+
+ if (dir0 == 5 || dir0 == 3) {
+ unsigned char ccr3;
+ unsigned long flags;
+ pr_info("Enabling CPUID on Cyrix processor.\n");
+ local_irq_save(flags);
+ ccr3 = getCx86(CX86_CCR3);
+ /* enable MAPEN */
+ setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
+ /* enable cpuid */
+ setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x80);
+ /* disable MAPEN */
+ setCx86(CX86_CCR3, ccr3);
+ local_irq_restore(flags);
+ }
+ }
+}
+
+static const struct cpu_dev cyrix_cpu_dev = {
+ .c_vendor = "Cyrix",
+ .c_ident = { "CyrixInstead" },
+ .c_early_init = early_init_cyrix,
+ .c_init = init_cyrix,
+ .c_identify = cyrix_identify,
+ .c_x86_vendor = X86_VENDOR_CYRIX,
+};
+
+cpu_dev_register(cyrix_cpu_dev);
+
+static const struct cpu_dev nsc_cpu_dev = {
+ .c_vendor = "NSC",
+ .c_ident = { "Geode by NSC" },
+ .c_init = init_nsc,
+ .c_x86_vendor = X86_VENDOR_NSC,
+};
+
+cpu_dev_register(nsc_cpu_dev);