1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Driver for CPM (SCC/SMC) serial ports; CPM1 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/gfp.h>
17 #include <linux/ioport.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 <linux/of.h>
33 #include <linux/of_address.h>
34 
35 #include "cpm_uart.h"
36 
37 /**************************************************************/
38 
cpm_line_cr_cmd(struct uart_cpm_port * port,int cmd)39 void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
40 {
41 	cpm_command(port->command, cmd);
42 }
43 
cpm_uart_map_pram(struct uart_cpm_port * port,struct device_node * np)44 void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
45 				struct device_node *np)
46 {
47 	return of_iomap(np, 1);
48 }
49 
cpm_uart_unmap_pram(struct uart_cpm_port * port,void __iomem * pram)50 void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
51 {
52 	iounmap(pram);
53 }
54 
55 /*
56  * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
57  * receive buffer descriptors from dual port ram, and a character
58  * buffer area from host mem. If we are allocating for the console we need
59  * to do it from bootmem
60  */
cpm_uart_allocbuf(struct uart_cpm_port * pinfo,unsigned int is_con)61 int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
62 {
63 	int dpmemsz, memsz;
64 	u8 *dp_mem;
65 	unsigned long dp_offset;
66 	u8 *mem_addr;
67 	dma_addr_t dma_addr = 0;
68 
69 	pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
70 
71 	dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
72 	dp_offset = cpm_dpalloc(dpmemsz, 8);
73 	if (IS_ERR_VALUE(dp_offset)) {
74 		printk(KERN_ERR
75 		       "cpm_uart_cpm1.c: could not allocate buffer descriptors\n");
76 		return -ENOMEM;
77 	}
78 	dp_mem = cpm_dpram_addr(dp_offset);
79 
80 	memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
81 	    L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
82 	if (is_con) {
83 		/* was hostalloc but changed cause it blows away the */
84 		/* large tlb mapping when pinning the kernel area    */
85 		mem_addr = (u8 *) cpm_dpram_addr(cpm_dpalloc(memsz, 8));
86 		dma_addr = (u32)cpm_dpram_phys(mem_addr);
87 	} else
88 		mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
89 					      GFP_KERNEL);
90 
91 	if (mem_addr == NULL) {
92 		cpm_dpfree(dp_offset);
93 		printk(KERN_ERR
94 		       "cpm_uart_cpm1.c: could not allocate coherent memory\n");
95 		return -ENOMEM;
96 	}
97 
98 	pinfo->dp_addr = dp_offset;
99 	pinfo->mem_addr = mem_addr;             /*  virtual address*/
100 	pinfo->dma_addr = dma_addr;             /*  physical address*/
101 	pinfo->mem_size = memsz;
102 
103 	pinfo->rx_buf = mem_addr;
104 	pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
105 						       * pinfo->rx_fifosize);
106 
107 	pinfo->rx_bd_base = (cbd_t __iomem __force *)dp_mem;
108 	pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
109 
110 	return 0;
111 }
112 
cpm_uart_freebuf(struct uart_cpm_port * pinfo)113 void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
114 {
115 	dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
116 							  pinfo->rx_fifosize) +
117 			  L1_CACHE_ALIGN(pinfo->tx_nrfifos *
118 					 pinfo->tx_fifosize), pinfo->mem_addr,
119 			  pinfo->dma_addr);
120 
121 	cpm_dpfree(pinfo->dp_addr);
122 }
123