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Gigabeat S: Make it a removable mass-storage device. Windows will assign a drive to only the main data partition by default. To access the bootloader partition instead, press 'Vol -' while it connects (in bootloader and firmware). Hopefully doesn't break anything for anyone.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@28972 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Michael Sevakis 2011-01-05 19:35:51 +00:00
parent f97b9f11e4
commit 89a7a8138e
5 changed files with 97 additions and 42 deletions
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44
firmware/target/arm/imx31/gigabeat-s/usb-gigabeat-s.c
View file

@ -19,7 +19,6 @@
*
****************************************************************************/
#include "config.h"
#include "cpu.h"
#include "system.h"
#include "kernel.h"
#include "ata.h"
@ -31,8 +30,10 @@
#include "ccm-imx31.h"
#include "avic-imx31.h"
#include "power-gigabeat-s.h"
#include <string.h>
static int usb_status = USB_EXTRACTED;
static bool bootloader_install_mode = false;
static void enable_transceiver(bool enable)
{
@ -106,6 +107,16 @@ void usb_enable(bool on)
void usb_attach(void)
{
bootloader_install_mode = false;
if (usb_core_driver_enabled(USB_DRIVER_MASS_STORAGE))
{
/* Check if this will be bootloader install mode, exposing the
* boot partition instead of the data partition */
bootloader_install_mode =
(button_status() & USB_BL_INSTALL_MODE_BTN) != 0;
}
usb_drv_attach();
}
@ -133,3 +144,34 @@ void usb_drv_usb_detect_event(void)
if (usb_drv_powered())
usb_status_event(USB_INSERTED);
}
/* Called when reading the MBR */
void usb_fix_mbr(unsigned char *mbr)
{
unsigned char* p = mbr + 0x1be;
char tmp[16];
/* The Gigabeat S factory partition table contains invalid values for the
"active" flag in the MBR. This prevents at least the Linux kernel
from accepting the partition table, so we fix it on-the-fly. */
p[0x00] &= 0x80;
p[0x10] &= 0x80;
p[0x20] &= 0x80;
p[0x30] &= 0x80;
if (bootloader_install_mode)
return;
/* Windows ignores the partition flags and mounts the first partition it
sees when the device reports itself as removable. Swap the partitions
so the data partition appears to be partition 0. Mark the boot
partition 0 as hidden and make it partition 1. */
/* Mark the first partition as hidden */
p[0x04] |= 0x10;
/* Swap first and second partitions */
memcpy(tmp, &p[0x00], 16);
memcpy(&p[0x00], &p[0x10], 16);
memcpy(&p[0x10], tmp, 16);
}

13
firmware/target/arm/imx31/gigabeat-s/usb-target.h
View file

@ -30,4 +30,17 @@ void usb_init_device(void);
/* Read the immediate state of the cable from the PMIC */
bool usb_plugged(void);
/** Sector read/write filters **/
/* Filter some things in the MBR - see usb-gigabeat-s.c */
void usb_fix_mbr(unsigned char *mbr);
#define USBSTOR_READ_SECTORS_FILTER() \
({ if (cur_cmd.sector == 0) \
usb_fix_mbr(cur_cmd.data[cur_cmd.data_select]); \
0; })
/* Disallow MBR writes entirely since it was "fixed" in usb_fix_mbr */
#define USBSTOR_WRITE_SECTORS_FILTER() \
({ cur_cmd.sector != 0 ? 0 : -1; })
#endif /* USB_TARGET */