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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hal.c (23237B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * hal.c - DIM2 HAL implementation
      4 * (MediaLB, Device Interface Macro IP, OS62420)
      5 *
      6 * Copyright (C) 2015-2016, Microchip Technology Germany II GmbH & Co. KG
      7 */
      8
      9/* Author: Andrey Shvetsov <andrey.shvetsov@k2l.de> */
     10
     11#include "hal.h"
     12#include "errors.h"
     13#include "reg.h"
     14#include <linux/stddef.h>
     15#include <linux/kernel.h>
     16#include <linux/io.h>
     17
     18/*
     19 * Size factor for isochronous DBR buffer.
     20 * Minimal value is 3.
     21 */
     22#define ISOC_DBR_FACTOR 3u
     23
     24/*
     25 * Number of 32-bit units for DBR map.
     26 *
     27 * 1: block size is 512, max allocation is 16K
     28 * 2: block size is 256, max allocation is 8K
     29 * 4: block size is 128, max allocation is 4K
     30 * 8: block size is 64, max allocation is 2K
     31 *
     32 * Min allocated space is block size.
     33 * Max possible allocated space is 32 blocks.
     34 */
     35#define DBR_MAP_SIZE 2
     36
     37/* -------------------------------------------------------------------------- */
     38/* not configurable area */
     39
     40#define CDT 0x00
     41#define ADT 0x40
     42#define MLB_CAT 0x80
     43#define AHB_CAT 0x88
     44
     45#define DBR_SIZE  (16 * 1024) /* specified by IP */
     46#define DBR_BLOCK_SIZE  (DBR_SIZE / 32 / DBR_MAP_SIZE)
     47
     48#define ROUND_UP_TO(x, d)  (DIV_ROUND_UP(x, (d)) * (d))
     49
     50/* -------------------------------------------------------------------------- */
     51/* generic helper functions and macros */
     52
     53static inline u32 bit_mask(u8 position)
     54{
     55	return (u32)1 << position;
     56}
     57
     58static inline bool dim_on_error(u8 error_id, const char *error_message)
     59{
     60	dimcb_on_error(error_id, error_message);
     61	return false;
     62}
     63
     64/* -------------------------------------------------------------------------- */
     65/* types and local variables */
     66
     67struct async_tx_dbr {
     68	u8 ch_addr;
     69	u16 rpc;
     70	u16 wpc;
     71	u16 rest_size;
     72	u16 sz_queue[CDT0_RPC_MASK + 1];
     73};
     74
     75struct lld_global_vars_t {
     76	bool dim_is_initialized;
     77	bool mcm_is_initialized;
     78	struct dim2_regs __iomem *dim2; /* DIM2 core base address */
     79	struct async_tx_dbr atx_dbr;
     80	u32 fcnt;
     81	u32 dbr_map[DBR_MAP_SIZE];
     82};
     83
     84static struct lld_global_vars_t g = { false };
     85
     86/* -------------------------------------------------------------------------- */
     87
     88static int dbr_get_mask_size(u16 size)
     89{
     90	int i;
     91
     92	for (i = 0; i < 6; i++)
     93		if (size <= (DBR_BLOCK_SIZE << i))
     94			return 1 << i;
     95	return 0;
     96}
     97
     98/**
     99 * alloc_dbr() - Allocates DBR memory.
    100 * @size: Allocating memory size.
    101 * Returns: Offset in DBR memory by success or DBR_SIZE if out of memory.
    102 */
    103static int alloc_dbr(u16 size)
    104{
    105	int mask_size;
    106	int i, block_idx = 0;
    107
    108	if (size <= 0)
    109		return DBR_SIZE; /* out of memory */
    110
    111	mask_size = dbr_get_mask_size(size);
    112	if (mask_size == 0)
    113		return DBR_SIZE; /* out of memory */
    114
    115	for (i = 0; i < DBR_MAP_SIZE; i++) {
    116		u32 const blocks = DIV_ROUND_UP(size, DBR_BLOCK_SIZE);
    117		u32 mask = ~((~(u32)0) << blocks);
    118
    119		do {
    120			if ((g.dbr_map[i] & mask) == 0) {
    121				g.dbr_map[i] |= mask;
    122				return block_idx * DBR_BLOCK_SIZE;
    123			}
    124			block_idx += mask_size;
    125			/* do shift left with 2 steps in case mask_size == 32 */
    126			mask <<= mask_size - 1;
    127		} while ((mask <<= 1) != 0);
    128	}
    129
    130	return DBR_SIZE; /* out of memory */
    131}
    132
    133static void free_dbr(int offs, int size)
    134{
    135	int block_idx = offs / DBR_BLOCK_SIZE;
    136	u32 const blocks = DIV_ROUND_UP(size, DBR_BLOCK_SIZE);
    137	u32 mask = ~((~(u32)0) << blocks);
    138
    139	mask <<= block_idx % 32;
    140	g.dbr_map[block_idx / 32] &= ~mask;
    141}
    142
    143/* -------------------------------------------------------------------------- */
    144
    145static void dim2_transfer_madr(u32 val)
    146{
    147	writel(val, &g.dim2->MADR);
    148
    149	/* wait for transfer completion */
    150	while ((readl(&g.dim2->MCTL) & 1) != 1)
    151		continue;
    152
    153	writel(0, &g.dim2->MCTL);   /* clear transfer complete */
    154}
    155
    156static void dim2_clear_dbr(u16 addr, u16 size)
    157{
    158	enum { MADR_TB_BIT = 30, MADR_WNR_BIT = 31 };
    159
    160	u16 const end_addr = addr + size;
    161	u32 const cmd = bit_mask(MADR_WNR_BIT) | bit_mask(MADR_TB_BIT);
    162
    163	writel(0, &g.dim2->MCTL);   /* clear transfer complete */
    164	writel(0, &g.dim2->MDAT0);
    165
    166	for (; addr < end_addr; addr++)
    167		dim2_transfer_madr(cmd | addr);
    168}
    169
    170static u32 dim2_read_ctr(u32 ctr_addr, u16 mdat_idx)
    171{
    172	dim2_transfer_madr(ctr_addr);
    173
    174	return readl((&g.dim2->MDAT0) + mdat_idx);
    175}
    176
    177static void dim2_write_ctr_mask(u32 ctr_addr, const u32 *mask, const u32 *value)
    178{
    179	enum { MADR_WNR_BIT = 31 };
    180
    181	writel(0, &g.dim2->MCTL);   /* clear transfer complete */
    182
    183	if (mask[0] != 0)
    184		writel(value[0], &g.dim2->MDAT0);
    185	if (mask[1] != 0)
    186		writel(value[1], &g.dim2->MDAT1);
    187	if (mask[2] != 0)
    188		writel(value[2], &g.dim2->MDAT2);
    189	if (mask[3] != 0)
    190		writel(value[3], &g.dim2->MDAT3);
    191
    192	writel(mask[0], &g.dim2->MDWE0);
    193	writel(mask[1], &g.dim2->MDWE1);
    194	writel(mask[2], &g.dim2->MDWE2);
    195	writel(mask[3], &g.dim2->MDWE3);
    196
    197	dim2_transfer_madr(bit_mask(MADR_WNR_BIT) | ctr_addr);
    198}
    199
    200static inline void dim2_write_ctr(u32 ctr_addr, const u32 *value)
    201{
    202	u32 const mask[4] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
    203
    204	dim2_write_ctr_mask(ctr_addr, mask, value);
    205}
    206
    207static inline void dim2_clear_ctr(u32 ctr_addr)
    208{
    209	u32 const value[4] = { 0, 0, 0, 0 };
    210
    211	dim2_write_ctr(ctr_addr, value);
    212}
    213
    214static void dim2_configure_cat(u8 cat_base, u8 ch_addr, u8 ch_type,
    215			       bool read_not_write)
    216{
    217	bool isoc_fce = ch_type == CAT_CT_VAL_ISOC;
    218	bool sync_mfe = ch_type == CAT_CT_VAL_SYNC;
    219	u16 const cat =
    220		(read_not_write << CAT_RNW_BIT) |
    221		(ch_type << CAT_CT_SHIFT) |
    222		(ch_addr << CAT_CL_SHIFT) |
    223		(isoc_fce << CAT_FCE_BIT) |
    224		(sync_mfe << CAT_MFE_BIT) |
    225		(false << CAT_MT_BIT) |
    226		(true << CAT_CE_BIT);
    227	u8 const ctr_addr = cat_base + ch_addr / 8;
    228	u8 const idx = (ch_addr % 8) / 2;
    229	u8 const shift = (ch_addr % 2) * 16;
    230	u32 mask[4] = { 0, 0, 0, 0 };
    231	u32 value[4] = { 0, 0, 0, 0 };
    232
    233	mask[idx] = (u32)0xFFFF << shift;
    234	value[idx] = cat << shift;
    235	dim2_write_ctr_mask(ctr_addr, mask, value);
    236}
    237
    238static void dim2_clear_cat(u8 cat_base, u8 ch_addr)
    239{
    240	u8 const ctr_addr = cat_base + ch_addr / 8;
    241	u8 const idx = (ch_addr % 8) / 2;
    242	u8 const shift = (ch_addr % 2) * 16;
    243	u32 mask[4] = { 0, 0, 0, 0 };
    244	u32 value[4] = { 0, 0, 0, 0 };
    245
    246	mask[idx] = (u32)0xFFFF << shift;
    247	dim2_write_ctr_mask(ctr_addr, mask, value);
    248}
    249
    250static void dim2_configure_cdt(u8 ch_addr, u16 dbr_address, u16 hw_buffer_size,
    251			       u16 packet_length)
    252{
    253	u32 cdt[4] = { 0, 0, 0, 0 };
    254
    255	if (packet_length)
    256		cdt[1] = ((packet_length - 1) << CDT1_BS_ISOC_SHIFT);
    257
    258	cdt[3] =
    259		((hw_buffer_size - 1) << CDT3_BD_SHIFT) |
    260		(dbr_address << CDT3_BA_SHIFT);
    261	dim2_write_ctr(CDT + ch_addr, cdt);
    262}
    263
    264static u16 dim2_rpc(u8 ch_addr)
    265{
    266	u32 cdt0 = dim2_read_ctr(CDT + ch_addr, 0);
    267
    268	return (cdt0 >> CDT0_RPC_SHIFT) & CDT0_RPC_MASK;
    269}
    270
    271static void dim2_clear_cdt(u8 ch_addr)
    272{
    273	u32 cdt[4] = { 0, 0, 0, 0 };
    274
    275	dim2_write_ctr(CDT + ch_addr, cdt);
    276}
    277
    278static void dim2_configure_adt(u8 ch_addr)
    279{
    280	u32 adt[4] = { 0, 0, 0, 0 };
    281
    282	adt[0] =
    283		(true << ADT0_CE_BIT) |
    284		(true << ADT0_LE_BIT) |
    285		(0 << ADT0_PG_BIT);
    286
    287	dim2_write_ctr(ADT + ch_addr, adt);
    288}
    289
    290static void dim2_clear_adt(u8 ch_addr)
    291{
    292	u32 adt[4] = { 0, 0, 0, 0 };
    293
    294	dim2_write_ctr(ADT + ch_addr, adt);
    295}
    296
    297static void dim2_start_ctrl_async(u8 ch_addr, u8 idx, u32 buf_addr,
    298				  u16 buffer_size)
    299{
    300	u8 const shift = idx * 16;
    301
    302	u32 mask[4] = { 0, 0, 0, 0 };
    303	u32 adt[4] = { 0, 0, 0, 0 };
    304
    305	mask[1] =
    306		bit_mask(ADT1_PS_BIT + shift) |
    307		bit_mask(ADT1_RDY_BIT + shift) |
    308		(ADT1_CTRL_ASYNC_BD_MASK << (ADT1_BD_SHIFT + shift));
    309	adt[1] =
    310		(true << (ADT1_PS_BIT + shift)) |
    311		(true << (ADT1_RDY_BIT + shift)) |
    312		((buffer_size - 1) << (ADT1_BD_SHIFT + shift));
    313
    314	mask[idx + 2] = 0xFFFFFFFF;
    315	adt[idx + 2] = buf_addr;
    316
    317	dim2_write_ctr_mask(ADT + ch_addr, mask, adt);
    318}
    319
    320static void dim2_start_isoc_sync(u8 ch_addr, u8 idx, u32 buf_addr,
    321				 u16 buffer_size)
    322{
    323	u8 const shift = idx * 16;
    324
    325	u32 mask[4] = { 0, 0, 0, 0 };
    326	u32 adt[4] = { 0, 0, 0, 0 };
    327
    328	mask[1] =
    329		bit_mask(ADT1_RDY_BIT + shift) |
    330		(ADT1_ISOC_SYNC_BD_MASK << (ADT1_BD_SHIFT + shift));
    331	adt[1] =
    332		(true << (ADT1_RDY_BIT + shift)) |
    333		((buffer_size - 1) << (ADT1_BD_SHIFT + shift));
    334
    335	mask[idx + 2] = 0xFFFFFFFF;
    336	adt[idx + 2] = buf_addr;
    337
    338	dim2_write_ctr_mask(ADT + ch_addr, mask, adt);
    339}
    340
    341static void dim2_clear_ctram(void)
    342{
    343	u32 ctr_addr;
    344
    345	for (ctr_addr = 0; ctr_addr < 0x90; ctr_addr++)
    346		dim2_clear_ctr(ctr_addr);
    347}
    348
    349static void dim2_configure_channel(
    350	u8 ch_addr, u8 type, u8 is_tx, u16 dbr_address, u16 hw_buffer_size,
    351	u16 packet_length)
    352{
    353	dim2_configure_cdt(ch_addr, dbr_address, hw_buffer_size, packet_length);
    354	dim2_configure_cat(MLB_CAT, ch_addr, type, is_tx ? 1 : 0);
    355
    356	dim2_configure_adt(ch_addr);
    357	dim2_configure_cat(AHB_CAT, ch_addr, type, is_tx ? 0 : 1);
    358
    359	/* unmask interrupt for used channel, enable mlb_sys_int[0] interrupt */
    360	writel(readl(&g.dim2->ACMR0) | bit_mask(ch_addr), &g.dim2->ACMR0);
    361}
    362
    363static void dim2_clear_channel(u8 ch_addr)
    364{
    365	/* mask interrupt for used channel, disable mlb_sys_int[0] interrupt */
    366	writel(readl(&g.dim2->ACMR0) & ~bit_mask(ch_addr), &g.dim2->ACMR0);
    367
    368	dim2_clear_cat(AHB_CAT, ch_addr);
    369	dim2_clear_adt(ch_addr);
    370
    371	dim2_clear_cat(MLB_CAT, ch_addr);
    372	dim2_clear_cdt(ch_addr);
    373
    374	/* clear channel status bit */
    375	writel(bit_mask(ch_addr), &g.dim2->ACSR0);
    376}
    377
    378/* -------------------------------------------------------------------------- */
    379/* trace async tx dbr fill state */
    380
    381static inline u16 norm_pc(u16 pc)
    382{
    383	return pc & CDT0_RPC_MASK;
    384}
    385
    386static void dbrcnt_init(u8 ch_addr, u16 dbr_size)
    387{
    388	g.atx_dbr.rest_size = dbr_size;
    389	g.atx_dbr.rpc = dim2_rpc(ch_addr);
    390	g.atx_dbr.wpc = g.atx_dbr.rpc;
    391}
    392
    393static void dbrcnt_enq(int buf_sz)
    394{
    395	g.atx_dbr.rest_size -= buf_sz;
    396	g.atx_dbr.sz_queue[norm_pc(g.atx_dbr.wpc)] = buf_sz;
    397	g.atx_dbr.wpc++;
    398}
    399
    400u16 dim_dbr_space(struct dim_channel *ch)
    401{
    402	u16 cur_rpc;
    403	struct async_tx_dbr *dbr = &g.atx_dbr;
    404
    405	if (ch->addr != dbr->ch_addr)
    406		return 0xFFFF;
    407
    408	cur_rpc = dim2_rpc(ch->addr);
    409
    410	while (norm_pc(dbr->rpc) != cur_rpc) {
    411		dbr->rest_size += dbr->sz_queue[norm_pc(dbr->rpc)];
    412		dbr->rpc++;
    413	}
    414
    415	if ((u16)(dbr->wpc - dbr->rpc) >= CDT0_RPC_MASK)
    416		return 0;
    417
    418	return dbr->rest_size;
    419}
    420
    421/* -------------------------------------------------------------------------- */
    422/* channel state helpers */
    423
    424static void state_init(struct int_ch_state *state)
    425{
    426	state->request_counter = 0;
    427	state->service_counter = 0;
    428
    429	state->idx1 = 0;
    430	state->idx2 = 0;
    431	state->level = 0;
    432}
    433
    434/* -------------------------------------------------------------------------- */
    435/* macro helper functions */
    436
    437static inline bool check_channel_address(u32 ch_address)
    438{
    439	return ch_address > 0 && (ch_address % 2) == 0 &&
    440	       (ch_address / 2) <= (u32)CAT_CL_MASK;
    441}
    442
    443static inline bool check_packet_length(u32 packet_length)
    444{
    445	u16 const max_size = ((u16)CDT3_BD_ISOC_MASK + 1u) / ISOC_DBR_FACTOR;
    446
    447	if (packet_length <= 0)
    448		return false; /* too small */
    449
    450	if (packet_length > max_size)
    451		return false; /* too big */
    452
    453	if (packet_length - 1u > (u32)CDT1_BS_ISOC_MASK)
    454		return false; /* too big */
    455
    456	return true;
    457}
    458
    459static inline bool check_bytes_per_frame(u32 bytes_per_frame)
    460{
    461	u16 const bd_factor = g.fcnt + 2;
    462	u16 const max_size = ((u16)CDT3_BD_MASK + 1u) >> bd_factor;
    463
    464	if (bytes_per_frame <= 0)
    465		return false; /* too small */
    466
    467	if (bytes_per_frame > max_size)
    468		return false; /* too big */
    469
    470	return true;
    471}
    472
    473u16 dim_norm_ctrl_async_buffer_size(u16 buf_size)
    474{
    475	u16 const max_size = (u16)ADT1_CTRL_ASYNC_BD_MASK + 1u;
    476
    477	if (buf_size > max_size)
    478		return max_size;
    479
    480	return buf_size;
    481}
    482
    483static inline u16 norm_isoc_buffer_size(u16 buf_size, u16 packet_length)
    484{
    485	u16 n;
    486	u16 const max_size = (u16)ADT1_ISOC_SYNC_BD_MASK + 1u;
    487
    488	if (buf_size > max_size)
    489		buf_size = max_size;
    490
    491	n = buf_size / packet_length;
    492
    493	if (n < 2u)
    494		return 0; /* too small buffer for given packet_length */
    495
    496	return packet_length * n;
    497}
    498
    499static inline u16 norm_sync_buffer_size(u16 buf_size, u16 bytes_per_frame)
    500{
    501	u16 n;
    502	u16 const max_size = (u16)ADT1_ISOC_SYNC_BD_MASK + 1u;
    503	u32 const unit = bytes_per_frame << g.fcnt;
    504
    505	if (buf_size > max_size)
    506		buf_size = max_size;
    507
    508	n = buf_size / unit;
    509
    510	if (n < 1u)
    511		return 0; /* too small buffer for given bytes_per_frame */
    512
    513	return unit * n;
    514}
    515
    516static void dim2_cleanup(void)
    517{
    518	/* disable MediaLB */
    519	writel(false << MLBC0_MLBEN_BIT, &g.dim2->MLBC0);
    520
    521	dim2_clear_ctram();
    522
    523	/* disable mlb_int interrupt */
    524	writel(0, &g.dim2->MIEN);
    525
    526	/* clear status for all dma channels */
    527	writel(0xFFFFFFFF, &g.dim2->ACSR0);
    528	writel(0xFFFFFFFF, &g.dim2->ACSR1);
    529
    530	/* mask interrupts for all channels */
    531	writel(0, &g.dim2->ACMR0);
    532	writel(0, &g.dim2->ACMR1);
    533}
    534
    535static void dim2_initialize(bool enable_6pin, u8 mlb_clock)
    536{
    537	dim2_cleanup();
    538
    539	/* configure and enable MediaLB */
    540	writel(enable_6pin << MLBC0_MLBPEN_BIT |
    541	       mlb_clock << MLBC0_MLBCLK_SHIFT |
    542	       g.fcnt << MLBC0_FCNT_SHIFT |
    543	       true << MLBC0_MLBEN_BIT,
    544	       &g.dim2->MLBC0);
    545
    546	/* activate all HBI channels */
    547	writel(0xFFFFFFFF, &g.dim2->HCMR0);
    548	writel(0xFFFFFFFF, &g.dim2->HCMR1);
    549
    550	/* enable HBI */
    551	writel(bit_mask(HCTL_EN_BIT), &g.dim2->HCTL);
    552
    553	/* configure DMA */
    554	writel(ACTL_DMA_MODE_VAL_DMA_MODE_1 << ACTL_DMA_MODE_BIT |
    555	       true << ACTL_SCE_BIT, &g.dim2->ACTL);
    556}
    557
    558static bool dim2_is_mlb_locked(void)
    559{
    560	u32 const mask0 = bit_mask(MLBC0_MLBLK_BIT);
    561	u32 const mask1 = bit_mask(MLBC1_CLKMERR_BIT) |
    562			  bit_mask(MLBC1_LOCKERR_BIT);
    563	u32 const c1 = readl(&g.dim2->MLBC1);
    564	u32 const nda_mask = (u32)MLBC1_NDA_MASK << MLBC1_NDA_SHIFT;
    565
    566	writel(c1 & nda_mask, &g.dim2->MLBC1);
    567	return (readl(&g.dim2->MLBC1) & mask1) == 0 &&
    568	       (readl(&g.dim2->MLBC0) & mask0) != 0;
    569}
    570
    571/* -------------------------------------------------------------------------- */
    572/* channel help routines */
    573
    574static inline bool service_channel(u8 ch_addr, u8 idx)
    575{
    576	u8 const shift = idx * 16;
    577	u32 const adt1 = dim2_read_ctr(ADT + ch_addr, 1);
    578	u32 mask[4] = { 0, 0, 0, 0 };
    579	u32 adt_w[4] = { 0, 0, 0, 0 };
    580
    581	if (((adt1 >> (ADT1_DNE_BIT + shift)) & 1) == 0)
    582		return false;
    583
    584	mask[1] =
    585		bit_mask(ADT1_DNE_BIT + shift) |
    586		bit_mask(ADT1_ERR_BIT + shift) |
    587		bit_mask(ADT1_RDY_BIT + shift);
    588	dim2_write_ctr_mask(ADT + ch_addr, mask, adt_w);
    589
    590	/* clear channel status bit */
    591	writel(bit_mask(ch_addr), &g.dim2->ACSR0);
    592
    593	return true;
    594}
    595
    596/* -------------------------------------------------------------------------- */
    597/* channel init routines */
    598
    599static void isoc_init(struct dim_channel *ch, u8 ch_addr, u16 packet_length)
    600{
    601	state_init(&ch->state);
    602
    603	ch->addr = ch_addr;
    604
    605	ch->packet_length = packet_length;
    606	ch->bytes_per_frame = 0;
    607	ch->done_sw_buffers_number = 0;
    608}
    609
    610static void sync_init(struct dim_channel *ch, u8 ch_addr, u16 bytes_per_frame)
    611{
    612	state_init(&ch->state);
    613
    614	ch->addr = ch_addr;
    615
    616	ch->packet_length = 0;
    617	ch->bytes_per_frame = bytes_per_frame;
    618	ch->done_sw_buffers_number = 0;
    619}
    620
    621static void channel_init(struct dim_channel *ch, u8 ch_addr)
    622{
    623	state_init(&ch->state);
    624
    625	ch->addr = ch_addr;
    626
    627	ch->packet_length = 0;
    628	ch->bytes_per_frame = 0;
    629	ch->done_sw_buffers_number = 0;
    630}
    631
    632/* returns true if channel interrupt state is cleared */
    633static bool channel_service_interrupt(struct dim_channel *ch)
    634{
    635	struct int_ch_state *const state = &ch->state;
    636
    637	if (!service_channel(ch->addr, state->idx2))
    638		return false;
    639
    640	state->idx2 ^= 1;
    641	state->request_counter++;
    642	return true;
    643}
    644
    645static bool channel_start(struct dim_channel *ch, u32 buf_addr, u16 buf_size)
    646{
    647	struct int_ch_state *const state = &ch->state;
    648
    649	if (buf_size <= 0)
    650		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE, "Bad buffer size");
    651
    652	if (ch->packet_length == 0 && ch->bytes_per_frame == 0 &&
    653	    buf_size != dim_norm_ctrl_async_buffer_size(buf_size))
    654		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE,
    655				    "Bad control/async buffer size");
    656
    657	if (ch->packet_length &&
    658	    buf_size != norm_isoc_buffer_size(buf_size, ch->packet_length))
    659		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE,
    660				    "Bad isochronous buffer size");
    661
    662	if (ch->bytes_per_frame &&
    663	    buf_size != norm_sync_buffer_size(buf_size, ch->bytes_per_frame))
    664		return dim_on_error(DIM_ERR_BAD_BUFFER_SIZE,
    665				    "Bad synchronous buffer size");
    666
    667	if (state->level >= 2u)
    668		return dim_on_error(DIM_ERR_OVERFLOW, "Channel overflow");
    669
    670	++state->level;
    671
    672	if (ch->addr == g.atx_dbr.ch_addr)
    673		dbrcnt_enq(buf_size);
    674
    675	if (ch->packet_length || ch->bytes_per_frame)
    676		dim2_start_isoc_sync(ch->addr, state->idx1, buf_addr, buf_size);
    677	else
    678		dim2_start_ctrl_async(ch->addr, state->idx1, buf_addr,
    679				      buf_size);
    680	state->idx1 ^= 1;
    681
    682	return true;
    683}
    684
    685static u8 channel_service(struct dim_channel *ch)
    686{
    687	struct int_ch_state *const state = &ch->state;
    688
    689	if (state->service_counter != state->request_counter) {
    690		state->service_counter++;
    691		if (state->level == 0)
    692			return DIM_ERR_UNDERFLOW;
    693
    694		--state->level;
    695		ch->done_sw_buffers_number++;
    696	}
    697
    698	return DIM_NO_ERROR;
    699}
    700
    701static bool channel_detach_buffers(struct dim_channel *ch, u16 buffers_number)
    702{
    703	if (buffers_number > ch->done_sw_buffers_number)
    704		return dim_on_error(DIM_ERR_UNDERFLOW, "Channel underflow");
    705
    706	ch->done_sw_buffers_number -= buffers_number;
    707	return true;
    708}
    709
    710/* -------------------------------------------------------------------------- */
    711/* API */
    712
    713u8 dim_startup(struct dim2_regs __iomem *dim_base_address, u32 mlb_clock,
    714	       u32 fcnt)
    715{
    716	g.dim_is_initialized = false;
    717
    718	if (!dim_base_address)
    719		return DIM_INIT_ERR_DIM_ADDR;
    720
    721	/* MediaLB clock: 0 - 256 fs, 1 - 512 fs, 2 - 1024 fs, 3 - 2048 fs */
    722	/* MediaLB clock: 4 - 3072 fs, 5 - 4096 fs, 6 - 6144 fs, 7 - 8192 fs */
    723	if (mlb_clock >= 8)
    724		return DIM_INIT_ERR_MLB_CLOCK;
    725
    726	if (fcnt > MLBC0_FCNT_MAX_VAL)
    727		return DIM_INIT_ERR_MLB_CLOCK;
    728
    729	g.dim2 = dim_base_address;
    730	g.fcnt = fcnt;
    731	g.dbr_map[0] = 0;
    732	g.dbr_map[1] = 0;
    733
    734	dim2_initialize(mlb_clock >= 3, mlb_clock);
    735
    736	g.dim_is_initialized = true;
    737
    738	return DIM_NO_ERROR;
    739}
    740
    741void dim_shutdown(void)
    742{
    743	g.dim_is_initialized = false;
    744	dim2_cleanup();
    745}
    746
    747bool dim_get_lock_state(void)
    748{
    749	return dim2_is_mlb_locked();
    750}
    751
    752static u8 init_ctrl_async(struct dim_channel *ch, u8 type, u8 is_tx,
    753			  u16 ch_address, u16 hw_buffer_size)
    754{
    755	if (!g.dim_is_initialized || !ch)
    756		return DIM_ERR_DRIVER_NOT_INITIALIZED;
    757
    758	if (!check_channel_address(ch_address))
    759		return DIM_INIT_ERR_CHANNEL_ADDRESS;
    760
    761	if (!ch->dbr_size)
    762		ch->dbr_size = ROUND_UP_TO(hw_buffer_size, DBR_BLOCK_SIZE);
    763	ch->dbr_addr = alloc_dbr(ch->dbr_size);
    764	if (ch->dbr_addr >= DBR_SIZE)
    765		return DIM_INIT_ERR_OUT_OF_MEMORY;
    766
    767	channel_init(ch, ch_address / 2);
    768
    769	dim2_configure_channel(ch->addr, type, is_tx,
    770			       ch->dbr_addr, ch->dbr_size, 0);
    771
    772	return DIM_NO_ERROR;
    773}
    774
    775void dim_service_mlb_int_irq(void)
    776{
    777	writel(0, &g.dim2->MS0);
    778	writel(0, &g.dim2->MS1);
    779}
    780
    781/*
    782 * Retrieves maximal possible correct buffer size for isochronous data type
    783 * conform to given packet length and not bigger than given buffer size.
    784 *
    785 * Returns non-zero correct buffer size or zero by error.
    786 */
    787u16 dim_norm_isoc_buffer_size(u16 buf_size, u16 packet_length)
    788{
    789	if (!check_packet_length(packet_length))
    790		return 0;
    791
    792	return norm_isoc_buffer_size(buf_size, packet_length);
    793}
    794
    795/*
    796 * Retrieves maximal possible correct buffer size for synchronous data type
    797 * conform to given bytes per frame and not bigger than given buffer size.
    798 *
    799 * Returns non-zero correct buffer size or zero by error.
    800 */
    801u16 dim_norm_sync_buffer_size(u16 buf_size, u16 bytes_per_frame)
    802{
    803	if (!check_bytes_per_frame(bytes_per_frame))
    804		return 0;
    805
    806	return norm_sync_buffer_size(buf_size, bytes_per_frame);
    807}
    808
    809u8 dim_init_control(struct dim_channel *ch, u8 is_tx, u16 ch_address,
    810		    u16 max_buffer_size)
    811{
    812	return init_ctrl_async(ch, CAT_CT_VAL_CONTROL, is_tx, ch_address,
    813			       max_buffer_size);
    814}
    815
    816u8 dim_init_async(struct dim_channel *ch, u8 is_tx, u16 ch_address,
    817		  u16 max_buffer_size)
    818{
    819	u8 ret = init_ctrl_async(ch, CAT_CT_VAL_ASYNC, is_tx, ch_address,
    820				 max_buffer_size);
    821
    822	if (is_tx && !g.atx_dbr.ch_addr) {
    823		g.atx_dbr.ch_addr = ch->addr;
    824		dbrcnt_init(ch->addr, ch->dbr_size);
    825		writel(bit_mask(20), &g.dim2->MIEN);
    826	}
    827
    828	return ret;
    829}
    830
    831u8 dim_init_isoc(struct dim_channel *ch, u8 is_tx, u16 ch_address,
    832		 u16 packet_length)
    833{
    834	if (!g.dim_is_initialized || !ch)
    835		return DIM_ERR_DRIVER_NOT_INITIALIZED;
    836
    837	if (!check_channel_address(ch_address))
    838		return DIM_INIT_ERR_CHANNEL_ADDRESS;
    839
    840	if (!check_packet_length(packet_length))
    841		return DIM_ERR_BAD_CONFIG;
    842
    843	if (!ch->dbr_size)
    844		ch->dbr_size = packet_length * ISOC_DBR_FACTOR;
    845	ch->dbr_addr = alloc_dbr(ch->dbr_size);
    846	if (ch->dbr_addr >= DBR_SIZE)
    847		return DIM_INIT_ERR_OUT_OF_MEMORY;
    848
    849	isoc_init(ch, ch_address / 2, packet_length);
    850
    851	dim2_configure_channel(ch->addr, CAT_CT_VAL_ISOC, is_tx, ch->dbr_addr,
    852			       ch->dbr_size, packet_length);
    853
    854	return DIM_NO_ERROR;
    855}
    856
    857u8 dim_init_sync(struct dim_channel *ch, u8 is_tx, u16 ch_address,
    858		 u16 bytes_per_frame)
    859{
    860	u16 bd_factor = g.fcnt + 2;
    861
    862	if (!g.dim_is_initialized || !ch)
    863		return DIM_ERR_DRIVER_NOT_INITIALIZED;
    864
    865	if (!check_channel_address(ch_address))
    866		return DIM_INIT_ERR_CHANNEL_ADDRESS;
    867
    868	if (!check_bytes_per_frame(bytes_per_frame))
    869		return DIM_ERR_BAD_CONFIG;
    870
    871	if (!ch->dbr_size)
    872		ch->dbr_size = bytes_per_frame << bd_factor;
    873	ch->dbr_addr = alloc_dbr(ch->dbr_size);
    874	if (ch->dbr_addr >= DBR_SIZE)
    875		return DIM_INIT_ERR_OUT_OF_MEMORY;
    876
    877	sync_init(ch, ch_address / 2, bytes_per_frame);
    878
    879	dim2_clear_dbr(ch->dbr_addr, ch->dbr_size);
    880	dim2_configure_channel(ch->addr, CAT_CT_VAL_SYNC, is_tx,
    881			       ch->dbr_addr, ch->dbr_size, 0);
    882
    883	return DIM_NO_ERROR;
    884}
    885
    886u8 dim_destroy_channel(struct dim_channel *ch)
    887{
    888	if (!g.dim_is_initialized || !ch)
    889		return DIM_ERR_DRIVER_NOT_INITIALIZED;
    890
    891	if (ch->addr == g.atx_dbr.ch_addr) {
    892		writel(0, &g.dim2->MIEN);
    893		g.atx_dbr.ch_addr = 0;
    894	}
    895
    896	dim2_clear_channel(ch->addr);
    897	if (ch->dbr_addr < DBR_SIZE)
    898		free_dbr(ch->dbr_addr, ch->dbr_size);
    899	ch->dbr_addr = DBR_SIZE;
    900
    901	return DIM_NO_ERROR;
    902}
    903
    904void dim_service_ahb_int_irq(struct dim_channel *const *channels)
    905{
    906	bool state_changed;
    907
    908	if (!g.dim_is_initialized) {
    909		dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED,
    910			     "DIM is not initialized");
    911		return;
    912	}
    913
    914	if (!channels) {
    915		dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED, "Bad channels");
    916		return;
    917	}
    918
    919	/*
    920	 * Use while-loop and a flag to make sure the age is changed back at
    921	 * least once, otherwise the interrupt may never come if CPU generates
    922	 * interrupt on changing age.
    923	 * This cycle runs not more than number of channels, because
    924	 * channel_service_interrupt() routine doesn't start the channel again.
    925	 */
    926	do {
    927		struct dim_channel *const *ch = channels;
    928
    929		state_changed = false;
    930
    931		while (*ch) {
    932			state_changed |= channel_service_interrupt(*ch);
    933			++ch;
    934		}
    935	} while (state_changed);
    936}
    937
    938u8 dim_service_channel(struct dim_channel *ch)
    939{
    940	if (!g.dim_is_initialized || !ch)
    941		return DIM_ERR_DRIVER_NOT_INITIALIZED;
    942
    943	return channel_service(ch);
    944}
    945
    946struct dim_ch_state_t *dim_get_channel_state(struct dim_channel *ch,
    947					     struct dim_ch_state_t *state_ptr)
    948{
    949	if (!ch || !state_ptr)
    950		return NULL;
    951
    952	state_ptr->ready = ch->state.level < 2;
    953	state_ptr->done_buffers = ch->done_sw_buffers_number;
    954
    955	return state_ptr;
    956}
    957
    958bool dim_enqueue_buffer(struct dim_channel *ch, u32 buffer_addr,
    959			u16 buffer_size)
    960{
    961	if (!ch)
    962		return dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED,
    963				    "Bad channel");
    964
    965	return channel_start(ch, buffer_addr, buffer_size);
    966}
    967
    968bool dim_detach_buffers(struct dim_channel *ch, u16 buffers_number)
    969{
    970	if (!ch)
    971		return dim_on_error(DIM_ERR_DRIVER_NOT_INITIALIZED,
    972				    "Bad channel");
    973
    974	return channel_detach_buffers(ch, buffers_number);
    975}