Commit | Line | Data |
---|---|---|
7063c0d9 | 1 | /* |
ca632f55 | 2 | * Special handling for DW core on Intel MID platform |
7063c0d9 | 3 | * |
197e96b4 | 4 | * Copyright (c) 2009, 2014 Intel Corporation. |
7063c0d9 FT |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms and conditions of the GNU General Public License, | |
8 | * version 2, as published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope it will be useful, but WITHOUT | |
11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
13 | * more details. | |
7063c0d9 FT |
14 | */ |
15 | ||
16 | #include <linux/dma-mapping.h> | |
17 | #include <linux/dmaengine.h> | |
18 | #include <linux/interrupt.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/spi/spi.h> | |
258aea76 | 21 | #include <linux/types.h> |
568a60ed | 22 | |
ca632f55 | 23 | #include "spi-dw.h" |
7063c0d9 FT |
24 | |
25 | #ifdef CONFIG_SPI_DW_MID_DMA | |
26 | #include <linux/intel_mid_dma.h> | |
27 | #include <linux/pci.h> | |
28 | ||
29 | struct mid_dma { | |
30 | struct intel_mid_dma_slave dmas_tx; | |
31 | struct intel_mid_dma_slave dmas_rx; | |
32 | }; | |
33 | ||
34 | static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param) | |
35 | { | |
36 | struct dw_spi *dws = param; | |
37 | ||
b89e9c87 | 38 | return dws->dma_dev == chan->device->dev; |
7063c0d9 FT |
39 | } |
40 | ||
41 | static int mid_spi_dma_init(struct dw_spi *dws) | |
42 | { | |
43 | struct mid_dma *dw_dma = dws->dma_priv; | |
b89e9c87 | 44 | struct pci_dev *dma_dev; |
7063c0d9 FT |
45 | struct intel_mid_dma_slave *rxs, *txs; |
46 | dma_cap_mask_t mask; | |
47 | ||
48 | /* | |
49 | * Get pci device for DMA controller, currently it could only | |
ea092455 | 50 | * be the DMA controller of Medfield |
7063c0d9 | 51 | */ |
b89e9c87 AS |
52 | dma_dev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL); |
53 | if (!dma_dev) | |
54 | return -ENODEV; | |
55 | ||
56 | dws->dma_dev = &dma_dev->dev; | |
7063c0d9 FT |
57 | |
58 | dma_cap_zero(mask); | |
59 | dma_cap_set(DMA_SLAVE, mask); | |
60 | ||
61 | /* 1. Init rx channel */ | |
62 | dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, dws); | |
63 | if (!dws->rxchan) | |
64 | goto err_exit; | |
65 | rxs = &dw_dma->dmas_rx; | |
66 | rxs->hs_mode = LNW_DMA_HW_HS; | |
67 | rxs->cfg_mode = LNW_DMA_PER_TO_MEM; | |
68 | dws->rxchan->private = rxs; | |
69 | ||
70 | /* 2. Init tx channel */ | |
71 | dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, dws); | |
72 | if (!dws->txchan) | |
73 | goto free_rxchan; | |
74 | txs = &dw_dma->dmas_tx; | |
75 | txs->hs_mode = LNW_DMA_HW_HS; | |
76 | txs->cfg_mode = LNW_DMA_MEM_TO_PER; | |
77 | dws->txchan->private = txs; | |
78 | ||
79 | dws->dma_inited = 1; | |
80 | return 0; | |
81 | ||
82 | free_rxchan: | |
83 | dma_release_channel(dws->rxchan); | |
84 | err_exit: | |
b89e9c87 | 85 | return -EBUSY; |
7063c0d9 FT |
86 | } |
87 | ||
88 | static void mid_spi_dma_exit(struct dw_spi *dws) | |
89 | { | |
fb57862e AS |
90 | if (!dws->dma_inited) |
91 | return; | |
8e45ef68 AS |
92 | |
93 | dmaengine_terminate_all(dws->txchan); | |
7063c0d9 | 94 | dma_release_channel(dws->txchan); |
8e45ef68 AS |
95 | |
96 | dmaengine_terminate_all(dws->rxchan); | |
7063c0d9 FT |
97 | dma_release_channel(dws->rxchan); |
98 | } | |
99 | ||
100 | /* | |
101 | * dws->dma_chan_done is cleared before the dma transfer starts, | |
102 | * callback for rx/tx channel will each increment it by 1. | |
103 | * Reaching 2 means the whole spi transaction is done. | |
104 | */ | |
105 | static void dw_spi_dma_done(void *arg) | |
106 | { | |
107 | struct dw_spi *dws = arg; | |
108 | ||
109 | if (++dws->dma_chan_done != 2) | |
110 | return; | |
111 | dw_spi_xfer_done(dws); | |
112 | } | |
113 | ||
114 | static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change) | |
115 | { | |
2a285299 | 116 | struct dma_async_tx_descriptor *txdesc, *rxdesc; |
7063c0d9 FT |
117 | struct dma_slave_config txconf, rxconf; |
118 | u16 dma_ctrl = 0; | |
119 | ||
120 | /* 1. setup DMA related registers */ | |
121 | if (cs_change) { | |
122 | spi_enable_chip(dws, 0); | |
7eb187b3 HS |
123 | dw_writew(dws, DW_SPI_DMARDLR, 0xf); |
124 | dw_writew(dws, DW_SPI_DMATDLR, 0x10); | |
7063c0d9 | 125 | if (dws->tx_dma) |
15ee3be7 | 126 | dma_ctrl |= SPI_DMA_TDMAE; |
7063c0d9 | 127 | if (dws->rx_dma) |
15ee3be7 | 128 | dma_ctrl |= SPI_DMA_RDMAE; |
7eb187b3 | 129 | dw_writew(dws, DW_SPI_DMACR, dma_ctrl); |
7063c0d9 FT |
130 | spi_enable_chip(dws, 1); |
131 | } | |
132 | ||
133 | dws->dma_chan_done = 0; | |
7063c0d9 FT |
134 | |
135 | /* 2. Prepare the TX dma transfer */ | |
a485df4b | 136 | txconf.direction = DMA_MEM_TO_DEV; |
7063c0d9 FT |
137 | txconf.dst_addr = dws->dma_addr; |
138 | txconf.dst_maxburst = LNW_DMA_MSIZE_16; | |
139 | txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; | |
b41583e7 | 140 | txconf.dst_addr_width = dws->dma_width; |
258aea76 | 141 | txconf.device_fc = false; |
7063c0d9 | 142 | |
2a285299 | 143 | dmaengine_slave_config(dws->txchan, &txconf); |
7063c0d9 FT |
144 | |
145 | memset(&dws->tx_sgl, 0, sizeof(dws->tx_sgl)); | |
146 | dws->tx_sgl.dma_address = dws->tx_dma; | |
147 | dws->tx_sgl.length = dws->len; | |
148 | ||
2a285299 | 149 | txdesc = dmaengine_prep_slave_sg(dws->txchan, |
7063c0d9 FT |
150 | &dws->tx_sgl, |
151 | 1, | |
a485df4b | 152 | DMA_MEM_TO_DEV, |
0776ae7b | 153 | DMA_PREP_INTERRUPT); |
7063c0d9 FT |
154 | txdesc->callback = dw_spi_dma_done; |
155 | txdesc->callback_param = dws; | |
156 | ||
157 | /* 3. Prepare the RX dma transfer */ | |
a485df4b | 158 | rxconf.direction = DMA_DEV_TO_MEM; |
7063c0d9 FT |
159 | rxconf.src_addr = dws->dma_addr; |
160 | rxconf.src_maxburst = LNW_DMA_MSIZE_16; | |
161 | rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; | |
b41583e7 | 162 | rxconf.src_addr_width = dws->dma_width; |
258aea76 | 163 | rxconf.device_fc = false; |
7063c0d9 | 164 | |
2a285299 | 165 | dmaengine_slave_config(dws->rxchan, &rxconf); |
7063c0d9 FT |
166 | |
167 | memset(&dws->rx_sgl, 0, sizeof(dws->rx_sgl)); | |
168 | dws->rx_sgl.dma_address = dws->rx_dma; | |
169 | dws->rx_sgl.length = dws->len; | |
170 | ||
2a285299 | 171 | rxdesc = dmaengine_prep_slave_sg(dws->rxchan, |
7063c0d9 FT |
172 | &dws->rx_sgl, |
173 | 1, | |
a485df4b | 174 | DMA_DEV_TO_MEM, |
0776ae7b | 175 | DMA_PREP_INTERRUPT); |
7063c0d9 FT |
176 | rxdesc->callback = dw_spi_dma_done; |
177 | rxdesc->callback_param = dws; | |
178 | ||
179 | /* rx must be started before tx due to spi instinct */ | |
2a285299 AS |
180 | dmaengine_submit(rxdesc); |
181 | dmaengine_submit(txdesc); | |
7063c0d9 FT |
182 | return 0; |
183 | } | |
184 | ||
185 | static struct dw_spi_dma_ops mid_dma_ops = { | |
186 | .dma_init = mid_spi_dma_init, | |
187 | .dma_exit = mid_spi_dma_exit, | |
188 | .dma_transfer = mid_spi_dma_transfer, | |
189 | }; | |
190 | #endif | |
191 | ||
ea092455 | 192 | /* Some specific info for SPI0 controller on Intel MID */ |
7063c0d9 FT |
193 | |
194 | /* HW info for MRST CLk Control Unit, one 32b reg */ | |
195 | #define MRST_SPI_CLK_BASE 100000000 /* 100m */ | |
196 | #define MRST_CLK_SPI0_REG 0xff11d86c | |
197 | #define CLK_SPI_BDIV_OFFSET 0 | |
198 | #define CLK_SPI_BDIV_MASK 0x00000007 | |
199 | #define CLK_SPI_CDIV_OFFSET 9 | |
200 | #define CLK_SPI_CDIV_MASK 0x00000e00 | |
201 | #define CLK_SPI_DISABLE_OFFSET 8 | |
202 | ||
203 | int dw_spi_mid_init(struct dw_spi *dws) | |
204 | { | |
7eb187b3 HS |
205 | void __iomem *clk_reg; |
206 | u32 clk_cdiv; | |
7063c0d9 FT |
207 | |
208 | clk_reg = ioremap_nocache(MRST_CLK_SPI0_REG, 16); | |
209 | if (!clk_reg) | |
210 | return -ENOMEM; | |
211 | ||
212 | /* get SPI controller operating freq info */ | |
213 | clk_cdiv = (readl(clk_reg) & CLK_SPI_CDIV_MASK) >> CLK_SPI_CDIV_OFFSET; | |
214 | dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1); | |
215 | iounmap(clk_reg); | |
216 | ||
217 | dws->num_cs = 16; | |
218 | dws->fifo_len = 40; /* FIFO has 40 words buffer */ | |
219 | ||
220 | #ifdef CONFIG_SPI_DW_MID_DMA | |
221 | dws->dma_priv = kzalloc(sizeof(struct mid_dma), GFP_KERNEL); | |
222 | if (!dws->dma_priv) | |
223 | return -ENOMEM; | |
224 | dws->dma_ops = &mid_dma_ops; | |
225 | #endif | |
226 | return 0; | |
227 | } |