1 /*
2  *  Copyright (C) 2013 Altera Corporation <www.altera.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <asm/io.h>
9 #include <asm/arch/freeze_controller.h>
10 #include <asm/arch/scan_manager.h>
11 
12 DECLARE_GLOBAL_DATA_PTR;
13 
14 static const struct socfpga_scan_manager *scan_manager_base =
15 		(void *)(SOCFPGA_SCANMGR_ADDRESS);
16 static const struct socfpga_freeze_controller *freeze_controller_base =
17 		(void *)(SOCFPGA_SYSMGR_ADDRESS + SYSMGR_FRZCTRL_ADDRESS);
18 
19 /*
20  * Function to check IO scan chain engine status and wait if the engine is
21  * is active. Poll the IO scan chain engine till maximum iteration reached.
22  */
23 static inline uint32_t scan_chain_engine_is_idle(uint32_t max_iter)
24 {
25 	uint32_t scanmgr_status;
26 
27 	scanmgr_status = readl(&scan_manager_base->stat);
28 
29 	/* Poll the engine until the scan engine is inactive */
30 	while (SCANMGR_STAT_ACTIVE_GET(scanmgr_status) ||
31 	      (SCANMGR_STAT_WFIFOCNT_GET(scanmgr_status) > 0)) {
32 		max_iter--;
33 		if (max_iter > 0)
34 			scanmgr_status = readl(&scan_manager_base->stat);
35 		else
36 			return 0;
37 	}
38 	return 1;
39 }
40 
41 /* Program HPS IO Scan Chain */
42 uint32_t scan_mgr_io_scan_chain_prg(
43 	uint32_t io_scan_chain_id,
44 	uint32_t io_scan_chain_len_in_bits,
45 	const uint32_t *iocsr_scan_chain)
46 {
47 	uint16_t tdi_tdo_header;
48 	uint32_t io_program_iter;
49 	uint32_t io_scan_chain_data_residual;
50 	uint32_t residual;
51 	uint32_t i;
52 	uint32_t index = 0;
53 
54 	/*
55 	 * De-assert reinit if the IO scan chain is intended for HIO. In
56 	 * this, its the chain 3.
57 	 */
58 	if (io_scan_chain_id == 3)
59 		clrbits_le32(&freeze_controller_base->hioctrl,
60 			     SYSMGR_FRZCTRL_HIOCTRL_DLLRST_MASK);
61 
62 	/*
63 	 * Check if the scan chain engine is inactive and the
64 	 * WFIFO is empty before enabling the IO scan chain
65 	 */
66 	if (!scan_chain_engine_is_idle(SCAN_MAX_DELAY))
67 		return 1;
68 
69 	/*
70 	 * Enable IO Scan chain based on scan chain id
71 	 * Note: only one chain can be enabled at a time
72 	 */
73 	setbits_le32(&scan_manager_base->en, 1 << io_scan_chain_id);
74 
75 	/*
76 	 * Calculate number of iteration needed for full 128-bit (4 x32-bits)
77 	 * bits shifting. Each TDI_TDO packet can shift in maximum 128-bits
78 	 */
79 	io_program_iter	= io_scan_chain_len_in_bits >>
80 		IO_SCAN_CHAIN_128BIT_SHIFT;
81 	io_scan_chain_data_residual = io_scan_chain_len_in_bits &
82 		IO_SCAN_CHAIN_128BIT_MASK;
83 
84 	/* Construct TDI_TDO packet for 128-bit IO scan chain (2 bytes) */
85 	tdi_tdo_header = TDI_TDO_HEADER_FIRST_BYTE |
86 		(TDI_TDO_MAX_PAYLOAD <<	TDI_TDO_HEADER_SECOND_BYTE_SHIFT);
87 
88 	/* Program IO scan chain in 128-bit iteration */
89 	for (i = 0; i < io_program_iter; i++) {
90 		/* write TDI_TDO packet header to scan manager */
91 		writel(tdi_tdo_header,	&scan_manager_base->fifo_double_byte);
92 
93 		/* calculate array index. Multiply by 4 as write 4 x 32bits */
94 		index = i * 4;
95 
96 		/* write 4 successive 32-bit IO scan chain data into WFIFO */
97 		writel(iocsr_scan_chain[index],
98 		       &scan_manager_base->fifo_quad_byte);
99 		writel(iocsr_scan_chain[index + 1],
100 		       &scan_manager_base->fifo_quad_byte);
101 		writel(iocsr_scan_chain[index + 2],
102 		       &scan_manager_base->fifo_quad_byte);
103 		writel(iocsr_scan_chain[index + 3],
104 		       &scan_manager_base->fifo_quad_byte);
105 
106 		/*
107 		 * Check if the scan chain engine has completed the
108 		 * IO scan chain data shifting
109 		 */
110 		if (!scan_chain_engine_is_idle(SCAN_MAX_DELAY))
111 			goto error;
112 	}
113 
114 	/* Calculate array index for final TDI_TDO packet */
115 	index = io_program_iter * 4;
116 
117 	/* Final TDI_TDO packet if any */
118 	if (io_scan_chain_data_residual) {
119 		/*
120 		 * Calculate number of quad bytes FIFO write
121 		 * needed for the final TDI_TDO packet
122 		 */
123 		io_program_iter	= io_scan_chain_data_residual >>
124 			IO_SCAN_CHAIN_32BIT_SHIFT;
125 
126 		/*
127 		 * Construct TDI_TDO packet for remaining IO
128 		 * scan chain (2 bytes)
129 		 */
130 		tdi_tdo_header	= TDI_TDO_HEADER_FIRST_BYTE |
131 			((io_scan_chain_data_residual - 1) <<
132 			TDI_TDO_HEADER_SECOND_BYTE_SHIFT);
133 
134 		/*
135 		 * Program the last part of IO scan chain write TDI_TDO packet
136 		 * header (2 bytes) to scan manager
137 		 */
138 		writel(tdi_tdo_header, &scan_manager_base->fifo_double_byte);
139 
140 		for (i = 0; i < io_program_iter; i++) {
141 			/*
142 			 * write remaining scan chain data into scan
143 			 * manager WFIFO with 4 bytes write
144 			*/
145 			writel(iocsr_scan_chain[index + i],
146 			       &scan_manager_base->fifo_quad_byte);
147 		}
148 
149 		index += io_program_iter;
150 		residual = io_scan_chain_data_residual &
151 			IO_SCAN_CHAIN_32BIT_MASK;
152 
153 		if (IO_SCAN_CHAIN_PAYLOAD_24BIT < residual) {
154 			/*
155 			 * write the last 4B scan chain data
156 			 * into scan manager WFIFO
157 			 */
158 			writel(iocsr_scan_chain[index],
159 			       &scan_manager_base->fifo_quad_byte);
160 		} else {
161 			/*
162 			 * write the remaining 1 - 3 bytes scan chain
163 			 * data into scan manager WFIFO byte by byte
164 			 * to prevent JTAG engine shifting unused data
165 			 * from the FIFO and mistaken the data as a
166 			 * valid command (even though unused bits are
167 			 * set to 0, but just to prevent hardware
168 			 * glitch)
169 			 */
170 			for (i = 0; i < residual; i += 8) {
171 				writel(((iocsr_scan_chain[index] >> i)
172 					& IO_SCAN_CHAIN_BYTE_MASK),
173 					&scan_manager_base->fifo_single_byte);
174 			}
175 		}
176 
177 		/*
178 		 * Check if the scan chain engine has completed the
179 		 * IO scan chain data shifting
180 		 */
181 		if (!scan_chain_engine_is_idle(SCAN_MAX_DELAY))
182 			goto error;
183 	}
184 
185 	/* Disable IO Scan chain when configuration done*/
186 	clrbits_le32(&scan_manager_base->en, 1 << io_scan_chain_id);
187 	return 0;
188 
189 error:
190 	/* Disable IO Scan chain when error detected */
191 	clrbits_le32(&scan_manager_base->en, 1 << io_scan_chain_id);
192 	return 1;
193 }
194 
195 int scan_mgr_configure_iocsr(void)
196 {
197 	int status = 0;
198 
199 	/* configure the IOCSR through scan chain */
200 	status |= scan_mgr_io_scan_chain_prg(0,
201 		CONFIG_HPS_IOCSR_SCANCHAIN0_LENGTH, iocsr_scan_chain0_table);
202 	status |= scan_mgr_io_scan_chain_prg(1,
203 		CONFIG_HPS_IOCSR_SCANCHAIN1_LENGTH, iocsr_scan_chain1_table);
204 	status |= scan_mgr_io_scan_chain_prg(2,
205 		CONFIG_HPS_IOCSR_SCANCHAIN2_LENGTH, iocsr_scan_chain2_table);
206 	status |= scan_mgr_io_scan_chain_prg(3,
207 		CONFIG_HPS_IOCSR_SCANCHAIN3_LENGTH, iocsr_scan_chain3_table);
208 	return status;
209 }
210