Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // |
| 3 | // Copyright (c) 2019 MediaTek Inc. |
| 4 | |
| 5 | #include <asm/barrier.h> |
| 6 | #include <linux/clk.h> |
| 7 | #include <linux/err.h> |
| 8 | #include <linux/io.h> |
AngeloGioacchino Del Regno | fad151d | 2023-01-04 12:53:40 +0100 | [diff] [blame] | 9 | #include <linux/iopoll.h> |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 10 | #include <linux/kernel.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/platform_device.h> |
AngeloGioacchino Del Regno | fad151d | 2023-01-04 12:53:40 +0100 | [diff] [blame] | 13 | #include <linux/time64.h> |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 14 | #include <linux/remoteproc/mtk_scp.h> |
| 15 | |
| 16 | #include "mtk_common.h" |
| 17 | |
AngeloGioacchino Del Regno | fad151d | 2023-01-04 12:53:40 +0100 | [diff] [blame] | 18 | #define SCP_TIMEOUT_US (2000 * USEC_PER_MSEC) |
| 19 | |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 20 | /** |
| 21 | * scp_ipi_register() - register an ipi function |
| 22 | * |
| 23 | * @scp: mtk_scp structure |
| 24 | * @id: IPI ID |
| 25 | * @handler: IPI handler |
| 26 | * @priv: private data for IPI handler |
| 27 | * |
| 28 | * Register an ipi function to receive ipi interrupt from SCP. |
| 29 | * |
Arnaud Pouliquen | 8f86e69 | 2021-12-06 20:18:58 +0100 | [diff] [blame] | 30 | * Return: 0 if ipi registers successfully, -error on error. |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 31 | */ |
| 32 | int scp_ipi_register(struct mtk_scp *scp, |
| 33 | u32 id, |
| 34 | scp_ipi_handler_t handler, |
| 35 | void *priv) |
| 36 | { |
Colin Ian King | 434ac4d | 2020-09-18 16:24:28 +0100 | [diff] [blame] | 37 | if (!scp) |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 38 | return -EPROBE_DEFER; |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 39 | |
| 40 | if (WARN_ON(id >= SCP_IPI_MAX) || WARN_ON(handler == NULL)) |
| 41 | return -EINVAL; |
| 42 | |
| 43 | scp_ipi_lock(scp, id); |
| 44 | scp->ipi_desc[id].handler = handler; |
| 45 | scp->ipi_desc[id].priv = priv; |
| 46 | scp_ipi_unlock(scp, id); |
| 47 | |
| 48 | return 0; |
| 49 | } |
| 50 | EXPORT_SYMBOL_GPL(scp_ipi_register); |
| 51 | |
| 52 | /** |
| 53 | * scp_ipi_unregister() - unregister an ipi function |
| 54 | * |
| 55 | * @scp: mtk_scp structure |
| 56 | * @id: IPI ID |
| 57 | * |
| 58 | * Unregister an ipi function to receive ipi interrupt from SCP. |
| 59 | */ |
| 60 | void scp_ipi_unregister(struct mtk_scp *scp, u32 id) |
| 61 | { |
| 62 | if (!scp) |
| 63 | return; |
| 64 | |
| 65 | if (WARN_ON(id >= SCP_IPI_MAX)) |
| 66 | return; |
| 67 | |
| 68 | scp_ipi_lock(scp, id); |
| 69 | scp->ipi_desc[id].handler = NULL; |
| 70 | scp->ipi_desc[id].priv = NULL; |
| 71 | scp_ipi_unlock(scp, id); |
| 72 | } |
| 73 | EXPORT_SYMBOL_GPL(scp_ipi_unregister); |
| 74 | |
| 75 | /* |
| 76 | * scp_memcpy_aligned() - Copy src to dst, where dst is in SCP SRAM region. |
| 77 | * |
| 78 | * @dst: Pointer to the destination buffer, should be in SCP SRAM region. |
| 79 | * @src: Pointer to the source buffer. |
| 80 | * @len: Length of the source buffer to be copied. |
| 81 | * |
| 82 | * Since AP access of SCP SRAM don't support byte write, this always write a |
| 83 | * full word at a time, and may cause some extra bytes to be written at the |
| 84 | * beginning & ending of dst. |
| 85 | */ |
| 86 | void scp_memcpy_aligned(void __iomem *dst, const void *src, unsigned int len) |
| 87 | { |
| 88 | void __iomem *ptr; |
| 89 | u32 val; |
| 90 | unsigned int i = 0, remain; |
| 91 | |
| 92 | if (!IS_ALIGNED((unsigned long)dst, 4)) { |
| 93 | ptr = (void __iomem *)ALIGN_DOWN((unsigned long)dst, 4); |
| 94 | i = 4 - (dst - ptr); |
| 95 | val = readl_relaxed(ptr); |
| 96 | memcpy((u8 *)&val + (4 - i), src, i); |
| 97 | writel_relaxed(val, ptr); |
| 98 | } |
| 99 | |
| 100 | __iowrite32_copy(dst + i, src + i, (len - i) / 4); |
| 101 | remain = (len - i) % 4; |
| 102 | |
| 103 | if (remain > 0) { |
| 104 | val = readl_relaxed(dst + len - remain); |
| 105 | memcpy(&val, src + len - remain, remain); |
| 106 | writel_relaxed(val, dst + len - remain); |
| 107 | } |
| 108 | } |
| 109 | EXPORT_SYMBOL_GPL(scp_memcpy_aligned); |
| 110 | |
| 111 | /** |
| 112 | * scp_ipi_lock() - Lock before operations of an IPI ID |
| 113 | * |
| 114 | * @scp: mtk_scp structure |
| 115 | * @id: IPI ID |
| 116 | * |
| 117 | * Note: This should not be used by drivers other than mtk_scp. |
| 118 | */ |
| 119 | void scp_ipi_lock(struct mtk_scp *scp, u32 id) |
| 120 | { |
| 121 | if (WARN_ON(id >= SCP_IPI_MAX)) |
| 122 | return; |
| 123 | mutex_lock(&scp->ipi_desc[id].lock); |
| 124 | } |
| 125 | EXPORT_SYMBOL_GPL(scp_ipi_lock); |
| 126 | |
| 127 | /** |
Yang Li | e1996799 | 2023-03-16 16:40:11 +0800 | [diff] [blame] | 128 | * scp_ipi_unlock() - Unlock after operations of an IPI ID |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 129 | * |
| 130 | * @scp: mtk_scp structure |
| 131 | * @id: IPI ID |
| 132 | * |
| 133 | * Note: This should not be used by drivers other than mtk_scp. |
| 134 | */ |
| 135 | void scp_ipi_unlock(struct mtk_scp *scp, u32 id) |
| 136 | { |
| 137 | if (WARN_ON(id >= SCP_IPI_MAX)) |
| 138 | return; |
| 139 | mutex_unlock(&scp->ipi_desc[id].lock); |
| 140 | } |
| 141 | EXPORT_SYMBOL_GPL(scp_ipi_unlock); |
| 142 | |
| 143 | /** |
| 144 | * scp_ipi_send() - send data from AP to scp. |
| 145 | * |
| 146 | * @scp: mtk_scp structure |
| 147 | * @id: IPI ID |
| 148 | * @buf: the data buffer |
| 149 | * @len: the data buffer length |
| 150 | * @wait: number of msecs to wait for ack. 0 to skip waiting. |
| 151 | * |
| 152 | * This function is thread-safe. When this function returns, |
| 153 | * SCP has received the data and starts the processing. |
| 154 | * When the processing completes, IPI handler registered |
| 155 | * by scp_ipi_register will be called in interrupt context. |
| 156 | * |
Arnaud Pouliquen | 8f86e69 | 2021-12-06 20:18:58 +0100 | [diff] [blame] | 157 | * Return: 0 if sending data successfully, -error on error. |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 158 | **/ |
| 159 | int scp_ipi_send(struct mtk_scp *scp, u32 id, void *buf, unsigned int len, |
| 160 | unsigned int wait) |
| 161 | { |
| 162 | struct mtk_share_obj __iomem *send_obj = scp->send_buf; |
AngeloGioacchino Del Regno | fad151d | 2023-01-04 12:53:40 +0100 | [diff] [blame] | 163 | u32 val; |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 164 | int ret; |
| 165 | |
| 166 | if (WARN_ON(id <= SCP_IPI_INIT) || WARN_ON(id >= SCP_IPI_MAX) || |
Pi-Hsun Shih | 7017996 | 2019-11-12 19:03:26 +0800 | [diff] [blame] | 167 | WARN_ON(id == SCP_IPI_NS_SERVICE) || |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 168 | WARN_ON(len > sizeof(send_obj->share_buf)) || WARN_ON(!buf)) |
| 169 | return -EINVAL; |
| 170 | |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 171 | ret = clk_prepare_enable(scp->clk); |
| 172 | if (ret) { |
| 173 | dev_err(scp->dev, "failed to enable clock\n"); |
Chen-Yu Tsai | e46ceea | 2023-01-04 16:31:10 +0800 | [diff] [blame] | 174 | return ret; |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 175 | } |
| 176 | |
Chen-Yu Tsai | e46ceea | 2023-01-04 16:31:10 +0800 | [diff] [blame] | 177 | mutex_lock(&scp->send_lock); |
| 178 | |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 179 | /* Wait until SCP receives the last command */ |
AngeloGioacchino Del Regno | fad151d | 2023-01-04 12:53:40 +0100 | [diff] [blame] | 180 | ret = readl_poll_timeout_atomic(scp->reg_base + scp->data->host_to_scp_reg, |
| 181 | val, !val, 0, SCP_TIMEOUT_US); |
| 182 | if (ret) { |
| 183 | dev_err(scp->dev, "%s: IPI timeout!\n", __func__); |
| 184 | goto unlock_mutex; |
| 185 | } |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 186 | |
| 187 | scp_memcpy_aligned(send_obj->share_buf, buf, len); |
| 188 | |
| 189 | writel(len, &send_obj->len); |
| 190 | writel(id, &send_obj->id); |
| 191 | |
| 192 | scp->ipi_id_ack[id] = false; |
| 193 | /* send the command to SCP */ |
Pi-Hsun Shih | fd0b6c1 | 2020-09-21 17:48:46 +0800 | [diff] [blame] | 194 | writel(scp->data->host_to_scp_int_bit, |
| 195 | scp->reg_base + scp->data->host_to_scp_reg); |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 196 | |
| 197 | if (wait) { |
| 198 | /* wait for SCP's ACK */ |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 199 | ret = wait_event_timeout(scp->ack_wq, |
| 200 | scp->ipi_id_ack[id], |
AngeloGioacchino Del Regno | ac8723e | 2023-01-04 12:53:41 +0100 | [diff] [blame] | 201 | msecs_to_jiffies(wait)); |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 202 | scp->ipi_id_ack[id] = false; |
| 203 | if (WARN(!ret, "scp ipi %d ack time out !", id)) |
| 204 | ret = -EIO; |
| 205 | else |
| 206 | ret = 0; |
| 207 | } |
| 208 | |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 209 | unlock_mutex: |
| 210 | mutex_unlock(&scp->send_lock); |
Chen-Yu Tsai | e46ceea | 2023-01-04 16:31:10 +0800 | [diff] [blame] | 211 | clk_disable_unprepare(scp->clk); |
Erin Lo | 63c13d6 | 2019-11-12 19:03:25 +0800 | [diff] [blame] | 212 | |
| 213 | return ret; |
| 214 | } |
| 215 | EXPORT_SYMBOL_GPL(scp_ipi_send); |
| 216 | |
| 217 | MODULE_LICENSE("GPL v2"); |
| 218 | MODULE_DESCRIPTION("MediaTek scp IPI interface"); |