Re: [PATCH] fix Intel RNG detection (take 2)

From: Michael Buesch
Date: Mon Jul 31 2006 - 06:46:24 EST

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In reply to: Jan Beulich: "[PATCH] fix Intel RNG detection (take 2)"
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On Monday 31 July 2006 12:41, Jan Beulich wrote:
> Previously, since determination whether there was an Intel random
> number generator was based on a single bit, on systems with a matching
> bridge device but without a firmware hub, there was a 50% chance that
> the code would incorrectly decide that the system had an RNG. This
> patch adds detection of the firmware hub to better qualify the
> existence of an RNG.
>
> There is one issue with the patch: I was unable to determine the LPC
> equivalent for the PCI bridge 8086:2430 (since the old code didn't
> care about which of the many devices provided by the ICH/ESB it was
> chose to use the PCI bridge device, but the FWH settings live in the
> LPC device, so the device list needed to be changed).
>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
> Cc: Michael Buesch <mb@xxxxxxxxx>

Acked-by: Michael Buesch <mb@xxxxxxxxx>

If noone else complains, Andrew please apply to -mm
and queue for the next kernel.

> --- /home/jbeulich/tmp/linux-2.6.18-rc3/drivers/char/hw_random/intel-rng.c 2006-07-31 08:54:30.000000000 +0200
> +++ 2.6.18-rc3-intel-rng/drivers/char/hw_random/intel-rng.c 2006-07-31 10:38:47.000000000 +0200
> @@ -50,6 +50,43 @@
> #define INTEL_RNG_ADDR_LEN 3
>
> /*
> + * LPC bridge PCI config space registers
> + */
> +#define FWH_DEC_EN1_REG_OLD 0xe3
> +#define FWH_DEC_EN1_REG_NEW 0xd9 /* high byte of 16-bit register */
> +#define FWH_F8_EN_MASK 0x80
> +
> +#define BIOS_CNTL_REG_OLD 0x4e
> +#define BIOS_CNTL_REG_NEW 0xdc
> +#define BIOS_CNTL_WRITE_ENABLE_MASK 0x01
> +#define BIOS_CNTL_LOCK_ENABLE_MASK 0x02
> +
> +/*
> + * Magic address at which Intel Firmware Hubs get accessed
> + */
> +#define INTEL_FWH_ADDR 0xffff0000
> +#define INTEL_FWH_ADDR_LEN 2
> +
> +/*
> + * Intel Firmware Hub command codes (write to any address inside the device)
> + */
> +#define INTEL_FWH_RESET_CMD 0xff /* aka READ_ARRAY */
> +#define INTEL_FWH_READ_ID_CMD 0x90
> +
> +/*
> + * Intel Firmware Hub Read ID command result addresses
> + */
> +#define INTEL_FWH_MANUFACTURER_CODE_ADDRESS 0x000000
> +#define INTEL_FWH_DEVICE_CODE_ADDRESS 0x000001
> +
> +/*
> + * Intel Firmware Hub Read ID command result values
> + */
> +#define INTEL_FWH_MANUFACTURER_CODE 0x89
> +#define INTEL_FWH_DEVICE_CODE_8M 0xac
> +#define INTEL_FWH_DEVICE_CODE_4M 0xad
> +
> +/*
> * Data for PCI driver interface
> *
> * This data only exists for exporting the supported
> @@ -58,12 +95,50 @@
> * want to register another driver on the same PCI id.
> */
> static const struct pci_device_id pci_tbl[] = {
> - { 0x8086, 0x2418, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
> - { 0x8086, 0x2428, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
> - { 0x8086, 0x2430, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
> - { 0x8086, 0x2448, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
> - { 0x8086, 0x244e, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
> - { 0x8086, 0x245e, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
> +/* AA
> + { 0x8086, 0x2418, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, */
> + { 0x8086, 0x2410, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* AA */
> +/* AB
> + { 0x8086, 0x2428, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, */
> + { 0x8086, 0x2420, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* AB */
> +/* ??
> + { 0x8086, 0x2430, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, */
> +/* BAM, CAM, DBM, FBM, GxM
> + { 0x8086, 0x2448, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, */
> + { 0x8086, 0x244c, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* BAM */
> + { 0x8086, 0x248c, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* CAM */
> + { 0x8086, 0x24cc, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* DBM */
> + { 0x8086, 0x2641, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* FBM */
> + { 0x8086, 0x27b9, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* GxM */
> + { 0x8086, 0x27bd, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* GxM DH */
> +/* BA, CA, DB, Ex, 6300, Fx, 631x/632x, Gx
> + { 0x8086, 0x244e, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, */
> + { 0x8086, 0x2440, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* BA */
> + { 0x8086, 0x2480, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* CA */
> + { 0x8086, 0x24c0, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* DB */
> + { 0x8086, 0x24d0, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* Ex */
> + { 0x8086, 0x25a1, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 6300 */
> + { 0x8086, 0x2640, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* Fx */
> + { 0x8086, 0x2670, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2671, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2672, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2673, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2674, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2675, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2676, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2677, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2678, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x2679, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x267a, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x267b, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x267c, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x267d, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x267e, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x267f, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* 631x/632x */
> + { 0x8086, 0x27b8, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* Gx */
> +/* E
> + { 0x8086, 0x245e, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, */
> + { 0x8086, 0x2450, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, /* E */
> { 0, }, /* terminate list */
> };
> MODULE_DEVICE_TABLE(pci, pci_tbl);
> @@ -138,22 +213,115 @@ static struct hwrng intel_rng = {
> };
>
>
> +#ifdef CONFIG_SMP
> +static char __initdata waitflag;
> +
> +static void __init intel_init_wait (void *unused)
> +{
> + while (waitflag) {
> + cpu_relax();
> + smp_rmb();
> + }
> +}
> +#endif
> +
> static int __init mod_init(void)
> {
> int err = -ENODEV;
> + unsigned i;
> + struct pci_dev *dev = NULL;
> void __iomem *mem;
> - u8 hw_status;
> -
> - if (!pci_dev_present(pci_tbl))
> + unsigned long flags;
> + u8 bios_cntl_off, fwh_dec_en1_off;
> + u8 bios_cntl_val = 0xff, fwh_dec_en1_val = 0xff;
> + u8 hw_status, mfc, dvc;
> +
> + for (i = 0; !dev && pci_tbl[i].vendor; ++i)
> + dev = pci_get_device(pci_tbl[i].vendor, pci_tbl[i].device, NULL);
> +
> + if (!dev)
> goto out; /* Device not found. */
>
> + /* Check for Intel 82802 */
> + if (dev->device < 0x2640) {
> + fwh_dec_en1_off = FWH_DEC_EN1_REG_OLD;
> + bios_cntl_off = BIOS_CNTL_REG_OLD;
> + }
> + else {
> + fwh_dec_en1_off = FWH_DEC_EN1_REG_NEW;
> + bios_cntl_off = BIOS_CNTL_REG_NEW;
> + }
> +
> + pci_read_config_byte(dev, fwh_dec_en1_off, &fwh_dec_en1_val);
> + pci_read_config_byte(dev, bios_cntl_off, &bios_cntl_val);
> +
> + mem = ioremap_nocache(INTEL_FWH_ADDR, INTEL_FWH_ADDR_LEN);
> + if (mem == NULL) {
> + pci_dev_put(dev);
> + err = -EBUSY;
> + goto out;
> + }
> +
> +#ifdef CONFIG_SMP
> + waitflag = 1;
> + smp_wmb();
> + if (smp_call_function(intel_init_wait, NULL, 1, 0) != 0) {
> + waitflag = 0;
> + smp_wmb();
> + pci_dev_put(dev);
> + printk(KERN_ERR PFX "cannot run on all processors\n");
> + err = -EAGAIN;
> + goto err_unmap;
> + }
> +#else
> +#define waitflag err
> +#endif
> + local_irq_save(flags);
> +
> + if (!(fwh_dec_en1_val & FWH_F8_EN_MASK))
> + pci_write_config_byte(dev,
> + fwh_dec_en1_off,
> + fwh_dec_en1_val | FWH_F8_EN_MASK);
> + if (!(bios_cntl_val
> + & (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK)))
> + pci_write_config_byte(dev,
> + bios_cntl_off,
> + bios_cntl_val | BIOS_CNTL_WRITE_ENABLE_MASK);
> +
> + writeb(INTEL_FWH_RESET_CMD, mem);
> + writeb(INTEL_FWH_READ_ID_CMD, mem);
> + mfc = readb(mem + INTEL_FWH_MANUFACTURER_CODE_ADDRESS);
> + dvc = readb(mem + INTEL_FWH_DEVICE_CODE_ADDRESS);
> + writeb(INTEL_FWH_RESET_CMD, mem);
> +
> + if (!(bios_cntl_val
> + & (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK)))
> + pci_write_config_byte(dev, bios_cntl_off, bios_cntl_val);
> + if (!(fwh_dec_en1_val & FWH_F8_EN_MASK))
> + pci_write_config_byte(dev, fwh_dec_en1_off, fwh_dec_en1_val);
> +
> + local_irq_restore(flags);
> + waitflag = 0;
> + smp_wmb();
> +
> + iounmap(mem);
> + pci_dev_put(dev);
> +
> + if (mfc != INTEL_FWH_MANUFACTURER_CODE
> + || (dvc != INTEL_FWH_DEVICE_CODE_8M
> + && dvc != INTEL_FWH_DEVICE_CODE_4M)) {
> + printk(KERN_ERR PFX "FWH not detected\n");
> + err = -ENODEV;
> + goto out;
> + }
> +
> err = -ENOMEM;
> mem = ioremap(INTEL_RNG_ADDR, INTEL_RNG_ADDR_LEN);
> if (!mem)
> goto out;
> intel_rng.priv = (unsigned long)mem;
>
> - /* Check for Intel 82802 */
> + /* Check for Random Number Generator */
> err = -ENODEV;
> hw_status = hwstatus_get(mem);
> if ((hw_status & INTEL_RNG_PRESENT) == 0)
>
>

--
Greetings Michael.
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Next message: Alan Cox: "Re: [2.6.18-rc2-mm1] libata: DMA speed too slow for cdrecord"
Previous message: Alan Cox: "Re: Fwd: PROBLEM: ide messages during boot caused by a strangepartition table"
In reply to: Jan Beulich: "[PATCH] fix Intel RNG detection (take 2)"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]