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 #include <asm/prom.h>
29
30 #include <linux/serial_core.h>
31 #include <linux/kernel.h>
32
33 #include "cpm_uart.h"
34
35 /**************************************************************/
36
cpm_line_cr_cmd(struct uart_cpm_port * port,int cmd)37 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
38 {
39 cpm_command(port->command, cmd);
40 }
41
cpm_uart_map_pram(struct uart_cpm_port * port,struct device_node * np)42 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
43 struct device_node *np)
44 {
45 void __iomem *pram;
46 unsigned long offset;
47 struct resource res;
48 resource_size_t len;
49
50 /* Don't remap parameter RAM if it has already been initialized
51 * during console setup.
52 */
53 if (IS_SMC(port) && port->smcup)
54 return port->smcup;
55 else if (!IS_SMC(port) && port->sccup)
56 return port->sccup;
57
58 if (of_address_to_resource(np, 1, &res))
59 return NULL;
60
61 len = resource_size(&res);
62 pram = ioremap(res.start, len);
63 if (!pram)
64 return NULL;
65
66 if (!IS_SMC(port))
67 return pram;
68
69 if (len != 2) {
70 printk(KERN_WARNING "cpm_uart[%d]: device tree references "
71 "SMC pram, using boot loader/wrapper pram mapping. "
72 "Please fix your device tree to reference the pram "
73 "base register instead.\n",
74 port->port.line);
75 return pram;
76 }
77
78 offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
79 out_be16(pram, offset);
80 iounmap(pram);
81 return cpm_muram_addr(offset);
82 }
83
cpm_uart_unmap_pram(struct uart_cpm_port * port,void __iomem * pram)84 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
85 {
86 if (!IS_SMC(port))
87 iounmap(pram);
88 }
89
90 /*
91 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
92 * receive buffer descriptors from dual port ram, and a character
93 * buffer area from host mem. If we are allocating for the console we need
94 * to do it from bootmem
95 */
cpm_uart_allocbuf(struct uart_cpm_port * pinfo,unsigned int is_con)96 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
97 {
98 int dpmemsz, memsz;
99 u8 __iomem *dp_mem;
100 unsigned long dp_offset;
101 u8 *mem_addr;
102 dma_addr_t dma_addr = 0;
103
104 pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
105
106 dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
107 dp_offset = cpm_dpalloc(dpmemsz, 8);
108 if (IS_ERR_VALUE(dp_offset)) {
109 printk(KERN_ERR
110 "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
111 return -ENOMEM;
112 }
113
114 dp_mem = cpm_dpram_addr(dp_offset);
115
116 memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
117 L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
118 if (is_con) {
119 mem_addr = kzalloc(memsz, GFP_NOWAIT);
120 dma_addr = virt_to_bus(mem_addr);
121 }
122 else
123 mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
124 GFP_KERNEL);
125
126 if (mem_addr == NULL) {
127 cpm_dpfree(dp_offset);
128 printk(KERN_ERR
129 "cpm_uart_cpm.c: could not allocate coherent memory\n");
130 return -ENOMEM;
131 }
132
133 pinfo->dp_addr = dp_offset;
134 pinfo->mem_addr = mem_addr;
135 pinfo->dma_addr = dma_addr;
136 pinfo->mem_size = memsz;
137
138 pinfo->rx_buf = mem_addr;
139 pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
140 * pinfo->rx_fifosize);
141
142 pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
143 pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
144
145 return 0;
146 }
147
cpm_uart_freebuf(struct uart_cpm_port * pinfo)148 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
149 {
150 dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
151 pinfo->rx_fifosize) +
152 L1_CACHE_ALIGN(pinfo->tx_nrfifos *
153 pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
154 pinfo->dma_addr);
155
156 cpm_dpfree(pinfo->dp_addr);
157 }
158