From 08388273a3c4e895bf7e10f356f66c2363cfe90b Mon Sep 17 00:00:00 2001 From: =?utf8?q?Herv=C3=A9=20Poussineau?= Date: Mon, 6 Feb 2012 22:29:02 +0100 Subject: [PATCH] fdc: take side count into account MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Floppies can be simple or double-sided. However, current code was only taking the common case into account (ie 2 sides). This repairs single-sided floppies, which where totally broken before this patch : for track > 0, wrong sector number was calculated, and data was read/written at wrong place on underlying device. Fortunately, only some 360 kB floppies are single-sided, so this bug was probably not seen much. Signed-off-by: Hervé Poussineau Signed-off-by: Kevin Wolf --- hw/fdc.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/hw/fdc.c b/hw/fdc.c index 38fad587cb..64e635a849 100644 --- a/hw/fdc.c +++ b/hw/fdc.c @@ -95,16 +95,19 @@ static void fd_init(FDrive *drv) drv->max_track = 0; } +#define NUM_SIDES(drv) ((drv)->flags & FDISK_DBL_SIDES ? 2 : 1) + static int fd_sector_calc(uint8_t head, uint8_t track, uint8_t sect, - uint8_t last_sect) + uint8_t last_sect, uint8_t num_sides) { - return (((track * 2) + head) * last_sect) + sect - 1; + return (((track * num_sides) + head) * last_sect) + sect - 1; } /* Returns current position, in sectors, for given drive */ static int fd_sector(FDrive *drv) { - return fd_sector_calc(drv->head, drv->track, drv->sect, drv->last_sect); + return fd_sector_calc(drv->head, drv->track, drv->sect, drv->last_sect, + NUM_SIDES(drv)); } /* Seek to a new position: @@ -135,7 +138,7 @@ static int fd_seek(FDrive *drv, uint8_t head, uint8_t track, uint8_t sect, drv->max_track, drv->last_sect); return 3; } - sector = fd_sector_calc(head, track, sect, drv->last_sect); + sector = fd_sector_calc(head, track, sect, drv->last_sect, NUM_SIDES(drv)); ret = 0; if (sector != fd_sector(drv)) { #if 0 @@ -1019,7 +1022,8 @@ static void fdctrl_start_transfer(FDCtrl *fdctrl, int direction) ks = fdctrl->fifo[4]; FLOPPY_DPRINTF("Start transfer at %d %d %02x %02x (%d)\n", GET_CUR_DRV(fdctrl), kh, kt, ks, - fd_sector_calc(kh, kt, ks, cur_drv->last_sect)); + fd_sector_calc(kh, kt, ks, cur_drv->last_sect, + NUM_SIDES(cur_drv))); switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & FD_CONFIG_EIS)) { case 2: /* sect too big */ @@ -1289,7 +1293,8 @@ static void fdctrl_format_sector(FDCtrl *fdctrl) ks = fdctrl->fifo[8]; FLOPPY_DPRINTF("format sector at %d %d %02x %02x (%d)\n", GET_CUR_DRV(fdctrl), kh, kt, ks, - fd_sector_calc(kh, kt, ks, cur_drv->last_sect)); + fd_sector_calc(kh, kt, ks, cur_drv->last_sect, + NUM_SIDES(cur_drv))); switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & FD_CONFIG_EIS)) { case 2: /* sect too big */ -- 2.11.4.GIT