1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Driver for CPM (SCC/SMC) serial ports; CPM2 definitions
4 *
5 * Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
6 * Pantelis Antoniou (panto@intracom.gr) (CPM1)
7 *
8 * Copyright (C) 2004 Freescale Semiconductor, Inc.
9 * (C) 2004 Intracom, S.A.
10 * (C) 2006 MontaVista Software, Inc.
11 * Vitaly Bordug <vbordug@ru.mvista.com>
12 */
13
14 #include <linux/module.h>
15 #include <linux/tty.h>
16 #include <linux/ioport.h>
17 #include <linux/slab.h>
18 #include <linux/serial.h>
19 #include <linux/console.h>
20 #include <linux/sysrq.h>
21 #include <linux/device.h>
22 #include <linux/memblock.h>
23 #include <linux/dma-mapping.h>
24
25 #include <asm/io.h>
26 #include <asm/irq.h>
27 #include <asm/fs_pd.h>
28
29 #include <linux/serial_core.h>
30 #include <linux/kernel.h>
31
32 #include "cpm_uart.h"
33
34 /**************************************************************/
35
cpm_line_cr_cmd(struct uart_cpm_port * port,int cmd)36 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
37 {
38 cpm_command(port->command, cmd);
39 }
40
cpm_uart_map_pram(struct uart_cpm_port * port,struct device_node * np)41 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
42 struct device_node *np)
43 {
44 void __iomem *pram;
45 unsigned long offset;
46 struct resource res;
47 resource_size_t len;
48
49 /* Don't remap parameter RAM if it has already been initialized
50 * during console setup.
51 */
52 if (IS_SMC(port) && port->smcup)
53 return port->smcup;
54 else if (!IS_SMC(port) && port->sccup)
55 return port->sccup;
56
57 if (of_address_to_resource(np, 1, &res))
58 return NULL;
59
60 len = resource_size(&res);
61 pram = ioremap(res.start, len);
62 if (!pram)
63 return NULL;
64
65 if (!IS_SMC(port))
66 return pram;
67
68 if (len != 2) {
69 printk(KERN_WARNING "cpm_uart[%d]: device tree references "
70 "SMC pram, using boot loader/wrapper pram mapping. "
71 "Please fix your device tree to reference the pram "
72 "base register instead.\n",
73 port->port.line);
74 return pram;
75 }
76
77 offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
78 out_be16(pram, offset);
79 iounmap(pram);
80 return cpm_muram_addr(offset);
81 }
82
cpm_uart_unmap_pram(struct uart_cpm_port * port,void __iomem * pram)83 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
84 {
85 if (!IS_SMC(port))
86 iounmap(pram);
87 }
88
89 /*
90 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
91 * receive buffer descriptors from dual port ram, and a character
92 * buffer area from host mem. If we are allocating for the console we need
93 * to do it from bootmem
94 */
cpm_uart_allocbuf(struct uart_cpm_port * pinfo,unsigned int is_con)95 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
96 {
97 int dpmemsz, memsz;
98 u8 __iomem *dp_mem;
99 unsigned long dp_offset;
100 u8 *mem_addr;
101 dma_addr_t dma_addr = 0;
102
103 pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
104
105 dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
106 dp_offset = cpm_dpalloc(dpmemsz, 8);
107 if (IS_ERR_VALUE(dp_offset)) {
108 printk(KERN_ERR
109 "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
110 return -ENOMEM;
111 }
112
113 dp_mem = cpm_dpram_addr(dp_offset);
114
115 memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
116 L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
117 if (is_con) {
118 mem_addr = kzalloc(memsz, GFP_NOWAIT);
119 dma_addr = virt_to_bus(mem_addr);
120 }
121 else
122 mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
123 GFP_KERNEL);
124
125 if (mem_addr == NULL) {
126 cpm_dpfree(dp_offset);
127 printk(KERN_ERR
128 "cpm_uart_cpm.c: could not allocate coherent memory\n");
129 return -ENOMEM;
130 }
131
132 pinfo->dp_addr = dp_offset;
133 pinfo->mem_addr = mem_addr;
134 pinfo->dma_addr = dma_addr;
135 pinfo->mem_size = memsz;
136
137 pinfo->rx_buf = mem_addr;
138 pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
139 * pinfo->rx_fifosize);
140
141 pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
142 pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
143
144 return 0;
145 }
146
cpm_uart_freebuf(struct uart_cpm_port * pinfo)147 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
148 {
149 dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
150 pinfo->rx_fifosize) +
151 L1_CACHE_ALIGN(pinfo->tx_nrfifos *
152 pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
153 pinfo->dma_addr);
154
155 cpm_dpfree(pinfo->dp_addr);
156 }
157