From 8847d42d7a025200bc6b7df37c007a7dd3071d11 Mon Sep 17 00:00:00 2001 From: Michael Schmitz Date: Sun, 27 Aug 2023 16:13:48 +1200 Subject: [PATCH] ata: pata_falcon: add data_swab option to byte-swap disk data Some users of pata_falcon on Q40 have IDE disks in default IDE little endian byte order, whereas legacy disks use host-native big-endian byte order as on the Atari Falcon. Add module parameter 'data_swab' to allow connecting drives with non-native data byte order. Drives selected by the data_swap bit mask will have their user data byte-swapped to host byte order, i.e. 'pata_falcon.data_swab=2' will byte-swap all user data on drive B, leaving data on drive A in native byte order. On Q40, drives on a second IDE interface may be added to the bit mask as bits 2 and 3. Default setting is no byte swapping, i.e. compatibility with the native Falcon or Q40 operating system disk format. Cc: William R Sowerbutts Cc: Finn Thain Cc: Geert Uytterhoeven Tested-by: William R Sowerbutts Signed-off-by: Michael Schmitz Reviewed-by: Sergey Shtylyov Reviewed-by: Geert Uytterhoeven Signed-off-by: Damien Le Moal --- drivers/ata/pata_falcon.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/ata/pata_falcon.c b/drivers/ata/pata_falcon.c index 4818d42f9a9a..0c2ae430f5aa 100644 --- a/drivers/ata/pata_falcon.c +++ b/drivers/ata/pata_falcon.c @@ -32,6 +32,11 @@ #define DRV_NAME "pata_falcon" #define DRV_VERSION "0.1.0" +static int pata_falcon_swap_mask; + +module_param_named(data_swab, pata_falcon_swap_mask, int, 0444); +MODULE_PARM_DESC(data_swab, "Data byte swap enable/disable bitmap (0x1==drive1, 0x2==drive2, 0x4==drive3, 0x8==drive4, default==0)"); + static const struct scsi_host_template pata_falcon_sht = { ATA_PIO_SHT(DRV_NAME), }; @@ -49,7 +54,7 @@ static unsigned int pata_falcon_data_xfer(struct ata_queued_cmd *qc, if (dev->class == ATA_DEV_ATA && cmd && !blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) - swap = 0; + swap = (uintptr_t)ap->private_data & BIT(dev->devno); /* Transfer multiple of 2 bytes */ if (rw == READ) { @@ -123,6 +128,7 @@ static int __init pata_falcon_init_one(struct platform_device *pdev) struct ata_host *host; struct ata_port *ap; void __iomem *base, *ctl_base; + int mask_shift = 0; /* Q40 & Falcon default */ int irq = 0, io_offset = 1, reg_shift = 2; /* Falcon defaults */ dev_info(&pdev->dev, "Atari Falcon and Q40/Q60 PATA controller\n"); @@ -193,6 +199,10 @@ static int __init pata_falcon_init_one(struct platform_device *pdev) ata_port_desc(ap, "cmd %px ctl %px data %px", base, ctl_base, ap->ioaddr.data_addr); + if (pdev->id > 0) + mask_shift = 2; + ap->private_data = (void *)(uintptr_t)(pata_falcon_swap_mask >> mask_shift); + irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (irq_res && irq_res->start > 0) { irq = irq_res->start; -- 2.11.0