cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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pata_oldpiix.c (7365B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 *    pata_oldpiix.c - Intel PATA/SATA controllers
      4 *
      5 *	(C) 2005 Red Hat
      6 *
      7 *    Some parts based on ata_piix.c by Jeff Garzik and others.
      8 *
      9 *    Early PIIX differs significantly from the later PIIX as it lacks
     10 *    SITRE and the slave timing registers. This means that you have to
     11 *    set timing per channel, or be clever. Libata tells us whenever it
     12 *    does drive selection and we use this to reload the timings.
     13 *
     14 *    Because of these behaviour differences PIIX gets its own driver module.
     15 */
     16
     17#include <linux/kernel.h>
     18#include <linux/module.h>
     19#include <linux/pci.h>
     20#include <linux/blkdev.h>
     21#include <linux/delay.h>
     22#include <linux/device.h>
     23#include <scsi/scsi_host.h>
     24#include <linux/libata.h>
     25#include <linux/ata.h>
     26
     27#define DRV_NAME	"pata_oldpiix"
     28#define DRV_VERSION	"0.5.5"
     29
     30/**
     31 *	oldpiix_pre_reset		-	probe begin
     32 *	@link: ATA link
     33 *	@deadline: deadline jiffies for the operation
     34 *
     35 *	Set up cable type and use generic probe init
     36 */
     37
     38static int oldpiix_pre_reset(struct ata_link *link, unsigned long deadline)
     39{
     40	struct ata_port *ap = link->ap;
     41	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
     42	static const struct pci_bits oldpiix_enable_bits[] = {
     43		{ 0x41U, 1U, 0x80UL, 0x80UL },	/* port 0 */
     44		{ 0x43U, 1U, 0x80UL, 0x80UL },	/* port 1 */
     45	};
     46
     47	if (!pci_test_config_bits(pdev, &oldpiix_enable_bits[ap->port_no]))
     48		return -ENOENT;
     49
     50	return ata_sff_prereset(link, deadline);
     51}
     52
     53/**
     54 *	oldpiix_set_piomode - Initialize host controller PATA PIO timings
     55 *	@ap: Port whose timings we are configuring
     56 *	@adev: Device whose timings we are configuring
     57 *
     58 *	Set PIO mode for device, in host controller PCI config space.
     59 *
     60 *	LOCKING:
     61 *	None (inherited from caller).
     62 */
     63
     64static void oldpiix_set_piomode (struct ata_port *ap, struct ata_device *adev)
     65{
     66	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
     67	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
     68	unsigned int idetm_port= ap->port_no ? 0x42 : 0x40;
     69	u16 idetm_data;
     70	int control = 0;
     71
     72	/*
     73	 *	See Intel Document 298600-004 for the timing programing rules
     74	 *	for PIIX/ICH. Note that the early PIIX does not have the slave
     75	 *	timing port at 0x44.
     76	 */
     77
     78	static const	 /* ISP  RTC */
     79	u8 timings[][2]	= { { 0, 0 },
     80			    { 0, 0 },
     81			    { 1, 0 },
     82			    { 2, 1 },
     83			    { 2, 3 }, };
     84
     85	if (pio > 1)
     86		control |= 1;	/* TIME */
     87	if (ata_pio_need_iordy(adev))
     88		control |= 2;	/* IE */
     89
     90	/* Intel specifies that the prefetch/posting is for disk only */
     91	if (adev->class == ATA_DEV_ATA)
     92		control |= 4;	/* PPE */
     93
     94	pci_read_config_word(dev, idetm_port, &idetm_data);
     95
     96	/*
     97	 * Set PPE, IE and TIME as appropriate.
     98	 * Clear the other drive's timing bits.
     99	 */
    100	if (adev->devno == 0) {
    101		idetm_data &= 0xCCE0;
    102		idetm_data |= control;
    103	} else {
    104		idetm_data &= 0xCC0E;
    105		idetm_data |= (control << 4);
    106	}
    107	idetm_data |= (timings[pio][0] << 12) |
    108			(timings[pio][1] << 8);
    109	pci_write_config_word(dev, idetm_port, idetm_data);
    110
    111	/* Track which port is configured */
    112	ap->private_data = adev;
    113}
    114
    115/**
    116 *	oldpiix_set_dmamode - Initialize host controller PATA DMA timings
    117 *	@ap: Port whose timings we are configuring
    118 *	@adev: Device to program
    119 *
    120 *	Set MWDMA mode for device, in host controller PCI config space.
    121 *
    122 *	LOCKING:
    123 *	None (inherited from caller).
    124 */
    125
    126static void oldpiix_set_dmamode (struct ata_port *ap, struct ata_device *adev)
    127{
    128	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
    129	u8 idetm_port		= ap->port_no ? 0x42 : 0x40;
    130	u16 idetm_data;
    131
    132	static const	 /* ISP  RTC */
    133	u8 timings[][2]	= { { 0, 0 },
    134			    { 0, 0 },
    135			    { 1, 0 },
    136			    { 2, 1 },
    137			    { 2, 3 }, };
    138
    139	/*
    140	 * MWDMA is driven by the PIO timings. We must also enable
    141	 * IORDY unconditionally along with TIME1. PPE has already
    142	 * been set when the PIO timing was set.
    143	 */
    144
    145	unsigned int mwdma	= adev->dma_mode - XFER_MW_DMA_0;
    146	unsigned int control;
    147	const unsigned int needed_pio[3] = {
    148		XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
    149	};
    150	int pio = needed_pio[mwdma] - XFER_PIO_0;
    151
    152	pci_read_config_word(dev, idetm_port, &idetm_data);
    153
    154	control = 3;	/* IORDY|TIME0 */
    155	/* Intel specifies that the PPE functionality is for disk only */
    156	if (adev->class == ATA_DEV_ATA)
    157		control |= 4;	/* PPE enable */
    158
    159	/* If the drive MWDMA is faster than it can do PIO then
    160	   we must force PIO into PIO0 */
    161
    162	if (adev->pio_mode < needed_pio[mwdma])
    163		/* Enable DMA timing only */
    164		control |= 8;	/* PIO cycles in PIO0 */
    165
    166	/* Mask out the relevant control and timing bits we will load. Also
    167	   clear the other drive TIME register as a precaution */
    168	if (adev->devno == 0) {
    169		idetm_data &= 0xCCE0;
    170		idetm_data |= control;
    171	} else {
    172		idetm_data &= 0xCC0E;
    173		idetm_data |= (control << 4);
    174	}
    175	idetm_data |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
    176	pci_write_config_word(dev, idetm_port, idetm_data);
    177
    178	/* Track which port is configured */
    179	ap->private_data = adev;
    180}
    181
    182/**
    183 *	oldpiix_qc_issue	-	command issue
    184 *	@qc: command pending
    185 *
    186 *	Called when the libata layer is about to issue a command. We wrap
    187 *	this interface so that we can load the correct ATA timings if
    188 *	necessary. Our logic also clears TIME0/TIME1 for the other device so
    189 *	that, even if we get this wrong, cycles to the other device will
    190 *	be made PIO0.
    191 */
    192
    193static unsigned int oldpiix_qc_issue(struct ata_queued_cmd *qc)
    194{
    195	struct ata_port *ap = qc->ap;
    196	struct ata_device *adev = qc->dev;
    197
    198	if (adev != ap->private_data) {
    199		oldpiix_set_piomode(ap, adev);
    200		if (ata_dma_enabled(adev))
    201			oldpiix_set_dmamode(ap, adev);
    202	}
    203	return ata_bmdma_qc_issue(qc);
    204}
    205
    206
    207static struct scsi_host_template oldpiix_sht = {
    208	ATA_BMDMA_SHT(DRV_NAME),
    209};
    210
    211static struct ata_port_operations oldpiix_pata_ops = {
    212	.inherits		= &ata_bmdma_port_ops,
    213	.qc_issue		= oldpiix_qc_issue,
    214	.cable_detect		= ata_cable_40wire,
    215	.set_piomode		= oldpiix_set_piomode,
    216	.set_dmamode		= oldpiix_set_dmamode,
    217	.prereset		= oldpiix_pre_reset,
    218};
    219
    220
    221/**
    222 *	oldpiix_init_one - Register PIIX ATA PCI device with kernel services
    223 *	@pdev: PCI device to register
    224 *	@ent: Entry in oldpiix_pci_tbl matching with @pdev
    225 *
    226 *	Called from kernel PCI layer.  We probe for combined mode (sigh),
    227 *	and then hand over control to libata, for it to do the rest.
    228 *
    229 *	LOCKING:
    230 *	Inherited from PCI layer (may sleep).
    231 *
    232 *	RETURNS:
    233 *	Zero on success, or -ERRNO value.
    234 */
    235
    236static int oldpiix_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
    237{
    238	static const struct ata_port_info info = {
    239		.flags		= ATA_FLAG_SLAVE_POSS,
    240		.pio_mask	= ATA_PIO4,
    241		.mwdma_mask	= ATA_MWDMA12_ONLY,
    242		.port_ops	= &oldpiix_pata_ops,
    243	};
    244	const struct ata_port_info *ppi[] = { &info, NULL };
    245
    246	ata_print_version_once(&pdev->dev, DRV_VERSION);
    247
    248	return ata_pci_bmdma_init_one(pdev, ppi, &oldpiix_sht, NULL, 0);
    249}
    250
    251static const struct pci_device_id oldpiix_pci_tbl[] = {
    252	{ PCI_VDEVICE(INTEL, 0x1230), },
    253
    254	{ }	/* terminate list */
    255};
    256
    257static struct pci_driver oldpiix_pci_driver = {
    258	.name			= DRV_NAME,
    259	.id_table		= oldpiix_pci_tbl,
    260	.probe			= oldpiix_init_one,
    261	.remove			= ata_pci_remove_one,
    262#ifdef CONFIG_PM_SLEEP
    263	.suspend		= ata_pci_device_suspend,
    264	.resume			= ata_pci_device_resume,
    265#endif
    266};
    267
    268module_pci_driver(oldpiix_pci_driver);
    269
    270MODULE_AUTHOR("Alan Cox");
    271MODULE_DESCRIPTION("SCSI low-level driver for early PIIX series controllers");
    272MODULE_LICENSE("GPL");
    273MODULE_DEVICE_TABLE(pci, oldpiix_pci_tbl);
    274MODULE_VERSION(DRV_VERSION);