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_radisys.c (6822B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 *    pata_radisys.c - Intel PATA/SATA controllers
      4 *
      5 *	(C) 2006 Red Hat <alan@lxorguk.ukuu.org.uk>
      6 *
      7 *    Some parts based on ata_piix.c by Jeff Garzik and others.
      8 *
      9 *    A PIIX relative, this device has a single ATA channel and no
     10 *    slave timings, SITRE or PPE. In that sense it is a close relative
     11 *    of the original PIIX. It does however support UDMA 33/66 per channel
     12 *    although no other modes/timings. Also lacking is 32bit I/O on the ATA
     13 *    port.
     14 */
     15
     16#include <linux/kernel.h>
     17#include <linux/module.h>
     18#include <linux/pci.h>
     19#include <linux/blkdev.h>
     20#include <linux/delay.h>
     21#include <linux/device.h>
     22#include <scsi/scsi_host.h>
     23#include <linux/libata.h>
     24#include <linux/ata.h>
     25
     26#define DRV_NAME	"pata_radisys"
     27#define DRV_VERSION	"0.4.4"
     28
     29/**
     30 *	radisys_set_piomode - Initialize host controller PATA PIO timings
     31 *	@ap: ATA port
     32 *	@adev: Device whose timings we are configuring
     33 *
     34 *	Set PIO mode for device, in host controller PCI config space.
     35 *
     36 *	LOCKING:
     37 *	None (inherited from caller).
     38 */
     39
     40static void radisys_set_piomode (struct ata_port *ap, struct ata_device *adev)
     41{
     42	unsigned int pio	= adev->pio_mode - XFER_PIO_0;
     43	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
     44	u16 idetm_data;
     45	int control = 0;
     46
     47	/*
     48	 *	See Intel Document 298600-004 for the timing programing rules
     49	 *	for PIIX/ICH. Note that the early PIIX does not have the slave
     50	 *	timing port at 0x44. The Radisys is a relative of the PIIX
     51	 *	but not the same so be careful.
     52	 */
     53
     54	static const	 /* ISP  RTC */
     55	u8 timings[][2]	= { { 0, 0 },	/* Check me */
     56			    { 0, 0 },
     57			    { 1, 1 },
     58			    { 2, 2 },
     59			    { 3, 3 }, };
     60
     61	if (pio > 0)
     62		control |= 1;	/* TIME1 enable */
     63	if (ata_pio_need_iordy(adev))
     64		control |= 2;	/* IE IORDY */
     65
     66	pci_read_config_word(dev, 0x40, &idetm_data);
     67
     68	/* Enable IE and TIME as appropriate. Clear the other
     69	   drive timing bits */
     70	idetm_data &= 0xCCCC;
     71	idetm_data |= (control << (4 * adev->devno));
     72	idetm_data |= (timings[pio][0] << 12) |
     73			(timings[pio][1] << 8);
     74	pci_write_config_word(dev, 0x40, idetm_data);
     75
     76	/* Track which port is configured */
     77	ap->private_data = adev;
     78}
     79
     80/**
     81 *	radisys_set_dmamode - Initialize host controller PATA DMA timings
     82 *	@ap: Port whose timings we are configuring
     83 *	@adev: Device to program
     84 *
     85 *	Set MWDMA mode for device, in host controller PCI config space.
     86 *
     87 *	LOCKING:
     88 *	None (inherited from caller).
     89 */
     90
     91static void radisys_set_dmamode (struct ata_port *ap, struct ata_device *adev)
     92{
     93	struct pci_dev *dev	= to_pci_dev(ap->host->dev);
     94	u16 idetm_data;
     95	u8 udma_enable;
     96
     97	static const	 /* ISP  RTC */
     98	u8 timings[][2]	= { { 0, 0 },
     99			    { 0, 0 },
    100			    { 1, 1 },
    101			    { 2, 2 },
    102			    { 3, 3 }, };
    103
    104	/*
    105	 * MWDMA is driven by the PIO timings. We must also enable
    106	 * IORDY unconditionally.
    107	 */
    108
    109	pci_read_config_word(dev, 0x40, &idetm_data);
    110	pci_read_config_byte(dev, 0x48, &udma_enable);
    111
    112	if (adev->dma_mode < XFER_UDMA_0) {
    113		unsigned int mwdma	= adev->dma_mode - XFER_MW_DMA_0;
    114		const unsigned int needed_pio[3] = {
    115			XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
    116		};
    117		int pio = needed_pio[mwdma] - XFER_PIO_0;
    118		int control = 3;	/* IORDY|TIME0 */
    119
    120		/* If the drive MWDMA is faster than it can do PIO then
    121		   we must force PIO0 for PIO cycles. */
    122
    123		if (adev->pio_mode < needed_pio[mwdma])
    124			control = 1;
    125
    126		/* Mask out the relevant control and timing bits we will load. Also
    127		   clear the other drive TIME register as a precaution */
    128
    129		idetm_data &= 0xCCCC;
    130		idetm_data |= control << (4 * adev->devno);
    131		idetm_data |= (timings[pio][0] << 12) | (timings[pio][1] << 8);
    132
    133		udma_enable &= ~(1 << adev->devno);
    134	} else {
    135		u8 udma_mode;
    136
    137		/* UDMA66 on: UDMA 33 and 66 are switchable via register 0x4A */
    138
    139		pci_read_config_byte(dev, 0x4A, &udma_mode);
    140
    141		if (adev->xfer_mode == XFER_UDMA_2)
    142			udma_mode &= ~(2 << (adev->devno * 4));
    143		else /* UDMA 4 */
    144			udma_mode |= (2 << (adev->devno * 4));
    145
    146		pci_write_config_byte(dev, 0x4A, udma_mode);
    147
    148		udma_enable |= (1 << adev->devno);
    149	}
    150	pci_write_config_word(dev, 0x40, idetm_data);
    151	pci_write_config_byte(dev, 0x48, udma_enable);
    152
    153	/* Track which port is configured */
    154	ap->private_data = adev;
    155}
    156
    157/**
    158 *	radisys_qc_issue	-	command issue
    159 *	@qc: command pending
    160 *
    161 *	Called when the libata layer is about to issue a command. We wrap
    162 *	this interface so that we can load the correct ATA timings if
    163 *	necessary. Our logic also clears TIME0/TIME1 for the other device so
    164 *	that, even if we get this wrong, cycles to the other device will
    165 *	be made PIO0.
    166 */
    167
    168static unsigned int radisys_qc_issue(struct ata_queued_cmd *qc)
    169{
    170	struct ata_port *ap = qc->ap;
    171	struct ata_device *adev = qc->dev;
    172
    173	if (adev != ap->private_data) {
    174		/* UDMA timing is not shared */
    175		if (adev->dma_mode < XFER_UDMA_0 || !ata_dma_enabled(adev)) {
    176			if (ata_dma_enabled(adev))
    177				radisys_set_dmamode(ap, adev);
    178			else if (adev->pio_mode)
    179				radisys_set_piomode(ap, adev);
    180		}
    181	}
    182	return ata_bmdma_qc_issue(qc);
    183}
    184
    185
    186static struct scsi_host_template radisys_sht = {
    187	ATA_BMDMA_SHT(DRV_NAME),
    188};
    189
    190static struct ata_port_operations radisys_pata_ops = {
    191	.inherits		= &ata_bmdma_port_ops,
    192	.qc_issue		= radisys_qc_issue,
    193	.cable_detect		= ata_cable_unknown,
    194	.set_piomode		= radisys_set_piomode,
    195	.set_dmamode		= radisys_set_dmamode,
    196};
    197
    198
    199/**
    200 *	radisys_init_one - Register PIIX ATA PCI device with kernel services
    201 *	@pdev: PCI device to register
    202 *	@ent: Entry in radisys_pci_tbl matching with @pdev
    203 *
    204 *	Called from kernel PCI layer.  We probe for combined mode (sigh),
    205 *	and then hand over control to libata, for it to do the rest.
    206 *
    207 *	LOCKING:
    208 *	Inherited from PCI layer (may sleep).
    209 *
    210 *	RETURNS:
    211 *	Zero on success, or -ERRNO value.
    212 */
    213
    214static int radisys_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
    215{
    216	static const struct ata_port_info info = {
    217		.flags		= ATA_FLAG_SLAVE_POSS,
    218		.pio_mask	= ATA_PIO4,
    219		.mwdma_mask	= ATA_MWDMA12_ONLY,
    220		.udma_mask	= ATA_UDMA24_ONLY,
    221		.port_ops	= &radisys_pata_ops,
    222	};
    223	const struct ata_port_info *ppi[] = { &info, NULL };
    224
    225	ata_print_version_once(&pdev->dev, DRV_VERSION);
    226
    227	return ata_pci_bmdma_init_one(pdev, ppi, &radisys_sht, NULL, 0);
    228}
    229
    230static const struct pci_device_id radisys_pci_tbl[] = {
    231	{ PCI_VDEVICE(RADISYS, 0x8201), },
    232
    233	{ }	/* terminate list */
    234};
    235
    236static struct pci_driver radisys_pci_driver = {
    237	.name			= DRV_NAME,
    238	.id_table		= radisys_pci_tbl,
    239	.probe			= radisys_init_one,
    240	.remove			= ata_pci_remove_one,
    241#ifdef CONFIG_PM_SLEEP
    242	.suspend		= ata_pci_device_suspend,
    243	.resume			= ata_pci_device_resume,
    244#endif
    245};
    246
    247module_pci_driver(radisys_pci_driver);
    248
    249MODULE_AUTHOR("Alan Cox");
    250MODULE_DESCRIPTION("SCSI low-level driver for Radisys R82600 controllers");
    251MODULE_LICENSE("GPL");
    252MODULE_DEVICE_TABLE(pci, radisys_pci_tbl);
    253MODULE_VERSION(DRV_VERSION);