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Diffstat (limited to '')
| -rw-r--r-- | arch/m68k/include/asm/mac_psc.h | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/arch/m68k/include/asm/mac_psc.h b/arch/m68k/include/asm/mac_psc.h new file mode 100644 index 000000000..86a5a5eab --- /dev/null +++ b/arch/m68k/include/asm/mac_psc.h @@ -0,0 +1,252 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Apple Peripheral System Controller (PSC) + * + * The PSC is used on the AV Macs to control IO functions not handled + * by the VIAs (Ethernet, DSP, SCC, Sound). This includes nine DMA + * channels. + * + * The first seven DMA channels appear to be "one-shot" and are actually + * sets of two channels; one member is active while the other is being + * configured, and then you flip the active member and start all over again. + * The one-shot channels are grouped together and are: + * + * 1. SCSI + * 2. Ethernet Read + * 3. Ethernet Write + * 4. Floppy Disk Controller + * 5. SCC Channel A Receive + * 6. SCC Channel B Receive + * 7. SCC Channel A Transmit + * + * The remaining two channels are handled somewhat differently. They appear + * to be closely tied and share one set of registers. They also seem to run + * continuously, although how you keep the buffer filled in this scenario is + * not understood as there seems to be only one input and one output buffer + * pointer. + * + * Much of this was extrapolated from what was known about the Ethernet + * registers and subsequently confirmed using MacsBug (ie by pinging the + * machine with easy-to-find patterns and looking for them in the DMA + * buffers, or by sending a file over the serial ports and finding the + * file in the buffers.) + * + * 1999-05-25 (jmt) + */ + +#define PSC_BASE (0x50F31000) + +/* + * The IER/IFR registers work like the VIA, except that it has 4 + * of them each on different interrupt levels, and each register + * set only seems to handle four interrupts instead of seven. + * + * To access a particular set of registers, add 0xn0 to the base + * where n = 3,4,5 or 6. + */ + +#define pIFRbase 0x100 +#define pIERbase 0x104 + +/* + * One-shot DMA control registers + */ + +#define PSC_MYSTERY 0x804 + +#define PSC_CTL_BASE 0xC00 + +#define PSC_SCSI_CTL 0xC00 +#define PSC_ENETRD_CTL 0xC10 +#define PSC_ENETWR_CTL 0xC20 +#define PSC_FDC_CTL 0xC30 +#define PSC_SCCA_CTL 0xC40 +#define PSC_SCCB_CTL 0xC50 +#define PSC_SCCATX_CTL 0xC60 + +/* + * DMA channels. Add +0x10 for the second channel in the set. + * You're supposed to use one channel while the other runs and + * then flip channels and do the whole thing again. + */ + +#define PSC_ADDR_BASE 0x1000 +#define PSC_LEN_BASE 0x1004 +#define PSC_CMD_BASE 0x1008 + +#define PSC_SET0 0x00 +#define PSC_SET1 0x10 + +#define PSC_SCSI_ADDR 0x1000 /* confirmed */ +#define PSC_SCSI_LEN 0x1004 /* confirmed */ +#define PSC_SCSI_CMD 0x1008 /* confirmed */ +#define PSC_ENETRD_ADDR 0x1020 /* confirmed */ +#define PSC_ENETRD_LEN 0x1024 /* confirmed */ +#define PSC_ENETRD_CMD 0x1028 /* confirmed */ +#define PSC_ENETWR_ADDR 0x1040 /* confirmed */ +#define PSC_ENETWR_LEN 0x1044 /* confirmed */ +#define PSC_ENETWR_CMD 0x1048 /* confirmed */ +#define PSC_FDC_ADDR 0x1060 /* strongly suspected */ +#define PSC_FDC_LEN 0x1064 /* strongly suspected */ +#define PSC_FDC_CMD 0x1068 /* strongly suspected */ +#define PSC_SCCA_ADDR 0x1080 /* confirmed */ +#define PSC_SCCA_LEN 0x1084 /* confirmed */ +#define PSC_SCCA_CMD 0x1088 /* confirmed */ +#define PSC_SCCB_ADDR 0x10A0 /* confirmed */ +#define PSC_SCCB_LEN 0x10A4 /* confirmed */ +#define PSC_SCCB_CMD 0x10A8 /* confirmed */ +#define PSC_SCCATX_ADDR 0x10C0 /* confirmed */ +#define PSC_SCCATX_LEN 0x10C4 /* confirmed */ +#define PSC_SCCATX_CMD 0x10C8 /* confirmed */ + +/* + * Free-running DMA registers. The only part known for sure are the bits in + * the control register, the buffer addresses and the buffer length. Everything + * else is anybody's guess. + * + * These registers seem to be mirrored every thirty-two bytes up until offset + * 0x300. It's safe to assume then that a new set of registers starts there. + */ + +#define PSC_SND_CTL 0x200 /* + * [ 16-bit ] + * Sound (Singer?) control register. + * + * bit 0 : ???? + * bit 1 : ???? + * bit 2 : Set to one to enable sound + * output. Possibly a mute flag. + * bit 3 : ???? + * bit 4 : ???? + * bit 5 : ???? + * bit 6 : Set to one to enable pass-thru + * audio. In this mode the audio data + * seems to appear in both the input + * buffer and the output buffer. + * bit 7 : Set to one to activate the + * sound input DMA or zero to + * disable it. + * bit 8 : Set to one to activate the + * sound output DMA or zero to + * disable it. + * bit 9 : \ + * bit 11 : | + * These two bits control the sample + * rate. Usually set to binary 10 and + * MacOS 8.0 says I'm at 48 KHz. Using + * a binary value of 01 makes things + * sound about 1/2 speed (24 KHz?) and + * binary 00 is slower still (22 KHz?) + * + * Setting this to 0x0000 is a good way to + * kill all DMA at boot time so that the + * PSC won't overwrite the kernel image + * with sound data. + */ + +/* + * 0x0202 - 0x0203 is unused. Writing there + * seems to clobber the control register. + */ + +#define PSC_SND_SOURCE 0x204 /* + * [ 32-bit ] + * Controls input source and volume: + * + * bits 12-15 : input source volume, 0 - F + * bits 16-19 : unknown, always 0x5 + * bits 20-23 : input source selection: + * 0x3 = CD Audio + * 0x4 = External Audio + * + * The volume is definitely not the general + * output volume as it doesn't affect the + * alert sound volume. + */ +#define PSC_SND_STATUS1 0x208 /* + * [ 32-bit ] + * Appears to be a read-only status register. + * The usual value is 0x00400002. + */ +#define PSC_SND_HUH3 0x20C /* + * [ 16-bit ] + * Unknown 16-bit value, always 0x0000. + */ +#define PSC_SND_BITS2GO 0x20E /* + * [ 16-bit ] + * Counts down to zero from some constant + * value. The value appears to be the + * number of _bits_ remaining before the + * buffer is full, which would make sense + * since Apple's docs say the sound DMA + * channels are 1 bit wide. + */ +#define PSC_SND_INADDR 0x210 /* + * [ 32-bit ] + * Address of the sound input DMA buffer + */ +#define PSC_SND_OUTADDR 0x214 /* + * [ 32-bit ] + * Address of the sound output DMA buffer + */ +#define PSC_SND_LEN 0x218 /* + * [ 16-bit ] + * Length of both buffers in eight-byte units. + */ +#define PSC_SND_HUH4 0x21A /* + * [ 16-bit ] + * Unknown, always 0x0000. + */ +#define PSC_SND_STATUS2 0x21C /* + * [ 16-bit ] + * Appears to e a read-only status register. + * The usual value is 0x0200. + */ +#define PSC_SND_HUH5 0x21E /* + * [ 16-bit ] + * Unknown, always 0x0000. + */ + +#ifndef __ASSEMBLY__ + +extern volatile __u8 *psc; + +extern void psc_register_interrupts(void); +extern void psc_irq_enable(int); +extern void psc_irq_disable(int); + +/* + * Access functions + */ + +static inline void psc_write_byte(int offset, __u8 data) +{ + *((volatile __u8 *)(psc + offset)) = data; +} + +static inline void psc_write_word(int offset, __u16 data) +{ + *((volatile __u16 *)(psc + offset)) = data; +} + +static inline void psc_write_long(int offset, __u32 data) +{ + *((volatile __u32 *)(psc + offset)) = data; +} + +static inline u8 psc_read_byte(int offset) +{ + return *((volatile __u8 *)(psc + offset)); +} + +static inline u16 psc_read_word(int offset) +{ + return *((volatile __u16 *)(psc + offset)); +} + +static inline u32 psc_read_long(int offset) +{ + return *((volatile __u32 *)(psc + offset)); +} + +#endif /* __ASSEMBLY__ */ |