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_efar.c (8201B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 *    pata_efar.c - EFAR PIIX clone controller driver
      4 *
      5 *	(C) 2005 Red Hat
      6 *	(C) 2009-2010 Bartlomiej Zolnierkiewicz
      7 *
      8 *    Some parts based on ata_piix.c by Jeff Garzik and others.
      9 *
     10 *    The EFAR is a PIIX4 clone with UDMA66 support. Unlike the later
     11 *    Intel ICH controllers the EFAR widened the UDMA mode register bits
     12 *    and doesn't require the funky clock selection.
     13 */
     14
     15#include <linux/kernel.h>
     16#include <linux/module.h>
     17#include <linux/pci.h>
     18#include <linux/blkdev.h>
     19#include <linux/delay.h>
     20#include <linux/device.h>
     21#include <scsi/scsi_host.h>
     22#include <linux/libata.h>
     23#include <linux/ata.h>
     24
     25#define DRV_NAME	"pata_efar"
     26#define DRV_VERSION	"0.4.5"
     27
     28/**
     29 *	efar_pre_reset	-	Enable bits
     30 *	@link: ATA link
     31 *	@deadline: deadline jiffies for the operation
     32 *
     33 *	Perform cable detection for the EFAR ATA interface. This is
     34 *	different to the PIIX arrangement
     35 */
     36
     37static int efar_pre_reset(struct ata_link *link, unsigned long deadline)
     38{
     39	static const struct pci_bits efar_enable_bits[] = {
     40		{ 0x41U, 1U, 0x80UL, 0x80UL },	/* port 0 */
     41		{ 0x43U, 1U, 0x80UL, 0x80UL },	/* port 1 */
     42	};
     43	struct ata_port *ap = link->ap;
     44	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
     45
     46	if (!pci_test_config_bits(pdev, &efar_enable_bits[ap->port_no]))
     47		return -ENOENT;
     48
     49	return ata_sff_prereset(link, deadline);
     50}
     51
     52/**
     53 *	efar_cable_detect	-	check for 40/80 pin
     54 *	@ap: Port
     55 *
     56 *	Perform cable detection for the EFAR ATA interface. This is
     57 *	different to the PIIX arrangement
     58 */
     59
     60static int efar_cable_detect(struct ata_port *ap)
     61{
     62	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
     63	u8 tmp;
     64
     65	pci_read_config_byte(pdev, 0x47, &tmp);
     66	if (tmp & (2 >> ap->port_no))
     67		return ATA_CBL_PATA40;
     68	return ATA_CBL_PATA80;
     69}
     70
     71static DEFINE_SPINLOCK(efar_lock);
     72
     73/**
     74 *	efar_set_piomode - Initialize host controller PATA PIO timings
     75 *	@ap: Port whose timings we are configuring
     76 *	@adev: Device to program
     77 *
     78 *	Set PIO mode for device, in host controller PCI config space.
     79 *
     80 *	LOCKING:
     81 *	None (inherited from caller).
     82 */
     83
     84static void efar_set_piomode (struct ata_port *ap, struct ata_device *adev)
     85{
     86	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
     87	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
     88	unsigned int master_port = ap->port_no ? 0x42 : 0x40;
     89	unsigned long flags;
     90	u16 master_data;
     91	u8 udma_enable;
     92	int control = 0;
     93
     94	/*
     95	 *	See Intel Document 298600-004 for the timing programing rules
     96	 *	for PIIX/ICH. The EFAR is a clone so very similar
     97	 */
     98
     99	static const	 /* ISP  RTC */
    100	u8 timings[][2]	= { { 0, 0 },
    101			    { 0, 0 },
    102			    { 1, 0 },
    103			    { 2, 1 },
    104			    { 2, 3 }, };
    105
    106	if (pio > 1)
    107		control |= 1;	/* TIME */
    108	if (ata_pio_need_iordy(adev))	/* PIO 3/4 require IORDY */
    109		control |= 2;	/* IE */
    110	/* Intel specifies that the prefetch/posting is for disk only */
    111	if (adev->class == ATA_DEV_ATA)
    112		control |= 4;	/* PPE */
    113
    114	spin_lock_irqsave(&efar_lock, flags);
    115
    116	pci_read_config_word(dev, master_port, &master_data);
    117
    118	/* Set PPE, IE, and TIME as appropriate */
    119	if (adev->devno == 0) {
    120		master_data &= 0xCCF0;
    121		master_data |= control;
    122		master_data |= (timings[pio][0] << 12) |
    123			(timings[pio][1] << 8);
    124	} else {
    125		int shift = 4 * ap->port_no;
    126		u8 slave_data;
    127
    128		master_data &= 0xFF0F;
    129		master_data |= (control << 4);
    130
    131		/* Slave timing in separate register */
    132		pci_read_config_byte(dev, 0x44, &slave_data);
    133		slave_data &= ap->port_no ? 0x0F : 0xF0;
    134		slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << shift;
    135		pci_write_config_byte(dev, 0x44, slave_data);
    136	}
    137
    138	master_data |= 0x4000;	/* Ensure SITRE is set */
    139	pci_write_config_word(dev, master_port, master_data);
    140
    141	pci_read_config_byte(dev, 0x48, &udma_enable);
    142	udma_enable &= ~(1 << (2 * ap->port_no + adev->devno));
    143	pci_write_config_byte(dev, 0x48, udma_enable);
    144	spin_unlock_irqrestore(&efar_lock, flags);
    145}
    146
    147/**
    148 *	efar_set_dmamode - Initialize host controller PATA DMA timings
    149 *	@ap: Port whose timings we are configuring
    150 *	@adev: Device to program
    151 *
    152 *	Set UDMA/MWDMA mode for device, in host controller PCI config space.
    153 *
    154 *	LOCKING:
    155 *	None (inherited from caller).
    156 */
    157
    158static void efar_set_dmamode (struct ata_port *ap, struct ata_device *adev)
    159{
    160	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
    161	u8 master_port		= ap->port_no ? 0x42 : 0x40;
    162	u16 master_data;
    163	u8 speed		= adev->dma_mode;
    164	int devid		= adev->devno + 2 * ap->port_no;
    165	unsigned long flags;
    166	u8 udma_enable;
    167
    168	static const	 /* ISP  RTC */
    169	u8 timings[][2]	= { { 0, 0 },
    170			    { 0, 0 },
    171			    { 1, 0 },
    172			    { 2, 1 },
    173			    { 2, 3 }, };
    174
    175	spin_lock_irqsave(&efar_lock, flags);
    176
    177	pci_read_config_word(dev, master_port, &master_data);
    178	pci_read_config_byte(dev, 0x48, &udma_enable);
    179
    180	if (speed >= XFER_UDMA_0) {
    181		unsigned int udma	= adev->dma_mode - XFER_UDMA_0;
    182		u16 udma_timing;
    183
    184		udma_enable |= (1 << devid);
    185
    186		/* Load the UDMA mode number */
    187		pci_read_config_word(dev, 0x4A, &udma_timing);
    188		udma_timing &= ~(7 << (4 * devid));
    189		udma_timing |= udma << (4 * devid);
    190		pci_write_config_word(dev, 0x4A, udma_timing);
    191	} else {
    192		/*
    193		 * MWDMA is driven by the PIO timings. We must also enable
    194		 * IORDY unconditionally along with TIME1. PPE has already
    195		 * been set when the PIO timing was set.
    196		 */
    197		unsigned int mwdma	= adev->dma_mode - XFER_MW_DMA_0;
    198		unsigned int control;
    199		u8 slave_data;
    200		const unsigned int needed_pio[3] = {
    201			XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
    202		};
    203		int pio = needed_pio[mwdma] - XFER_PIO_0;
    204
    205		control = 3;	/* IORDY|TIME1 */
    206
    207		/* If the drive MWDMA is faster than it can do PIO then
    208		   we must force PIO into PIO0 */
    209
    210		if (adev->pio_mode < needed_pio[mwdma])
    211			/* Enable DMA timing only */
    212			control |= 8;	/* PIO cycles in PIO0 */
    213
    214		if (adev->devno) {	/* Slave */
    215			master_data &= 0xFF4F;  /* Mask out IORDY|TIME1|DMAONLY */
    216			master_data |= control << 4;
    217			pci_read_config_byte(dev, 0x44, &slave_data);
    218			slave_data &= ap->port_no ? 0x0F : 0xF0;
    219			/* Load the matching timing */
    220			slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
    221			pci_write_config_byte(dev, 0x44, slave_data);
    222		} else { 	/* Master */
    223			master_data &= 0xCCF4;	/* Mask out IORDY|TIME1|DMAONLY
    224						   and master timing bits */
    225			master_data |= control;
    226			master_data |=
    227				(timings[pio][0] << 12) |
    228				(timings[pio][1] << 8);
    229		}
    230		udma_enable &= ~(1 << devid);
    231		pci_write_config_word(dev, master_port, master_data);
    232	}
    233	pci_write_config_byte(dev, 0x48, udma_enable);
    234	spin_unlock_irqrestore(&efar_lock, flags);
    235}
    236
    237static struct scsi_host_template efar_sht = {
    238	ATA_BMDMA_SHT(DRV_NAME),
    239};
    240
    241static struct ata_port_operations efar_ops = {
    242	.inherits		= &ata_bmdma_port_ops,
    243	.cable_detect		= efar_cable_detect,
    244	.set_piomode		= efar_set_piomode,
    245	.set_dmamode		= efar_set_dmamode,
    246	.prereset		= efar_pre_reset,
    247};
    248
    249
    250/**
    251 *	efar_init_one - Register EFAR ATA PCI device with kernel services
    252 *	@pdev: PCI device to register
    253 *	@ent: Entry in efar_pci_tbl matching with @pdev
    254 *
    255 *	Called from kernel PCI layer.
    256 *
    257 *	LOCKING:
    258 *	Inherited from PCI layer (may sleep).
    259 *
    260 *	RETURNS:
    261 *	Zero on success, or -ERRNO value.
    262 */
    263
    264static int efar_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
    265{
    266	static const struct ata_port_info info = {
    267		.flags		= ATA_FLAG_SLAVE_POSS,
    268		.pio_mask	= ATA_PIO4,
    269		.mwdma_mask	= ATA_MWDMA12_ONLY,
    270		.udma_mask 	= ATA_UDMA4,
    271		.port_ops	= &efar_ops,
    272	};
    273	const struct ata_port_info *ppi[] = { &info, &info };
    274
    275	ata_print_version_once(&pdev->dev, DRV_VERSION);
    276
    277	return ata_pci_bmdma_init_one(pdev, ppi, &efar_sht, NULL,
    278				      ATA_HOST_PARALLEL_SCAN);
    279}
    280
    281static const struct pci_device_id efar_pci_tbl[] = {
    282	{ PCI_VDEVICE(EFAR, 0x9130), },
    283
    284	{ }	/* terminate list */
    285};
    286
    287static struct pci_driver efar_pci_driver = {
    288	.name			= DRV_NAME,
    289	.id_table		= efar_pci_tbl,
    290	.probe			= efar_init_one,
    291	.remove			= ata_pci_remove_one,
    292#ifdef CONFIG_PM_SLEEP
    293	.suspend		= ata_pci_device_suspend,
    294	.resume			= ata_pci_device_resume,
    295#endif
    296};
    297
    298module_pci_driver(efar_pci_driver);
    299
    300MODULE_AUTHOR("Alan Cox");
    301MODULE_DESCRIPTION("SCSI low-level driver for EFAR PIIX clones");
    302MODULE_LICENSE("GPL");
    303MODULE_DEVICE_TABLE(pci, efar_pci_tbl);
    304MODULE_VERSION(DRV_VERSION);