xref: /FreeRTOS-Plus-TCP-v3.1.0/source/portable/NetworkInterface/Zynq/uncached_memory.c (revision 37bdfe577f3b728058de714e2e747d3c78803f26) 
1 /*
2  * FreeRTOS+TCP V3.1.0
3  * Copyright (C) 2022 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
4  *
5  * SPDX-License-Identifier: MIT
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy of
8  * this software and associated documentation files (the "Software"), to deal in
9  * the Software without restriction, including without limitation the rights to
10  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
11  * the Software, and to permit persons to whom the Software is furnished to do so,
12  * subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in all
15  * copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
19  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
20  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
21  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * http://aws.amazon.com/freertos
25  * http://www.FreeRTOS.org
26  */
27 
28 /*
29  * uncached_memory.c
30  *
31  * This module will declare 1 MB of memory and switch off the caching for it.
32  *
33  * pucGetUncachedMemory( ulSize ) returns a trunc of this memory with a length
34  * rounded up to a multiple of 4 KB.
35  *
36  * ucIsCachedMemory( pucBuffer ) returns non-zero if a given pointer is NOT
37  * within the range of the 1 MB non-cached memory.
38  *
39  */
40 
41 /*
42  * After "_end", 1 MB of uncached memory will be allocated for DMA transfers.
43  * Both the DMA descriptors as well as all EMAC TX-buffers will be allocated in
44  * uncached memory.
45  */
46 
47 /* Standard includes. */
48 #include <stdint.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 
52 /* FreeRTOS includes. */
53 #include "FreeRTOS.h"
54 #include "task.h"
55 #include "queue.h"
56 
57 /* FreeRTOS+TCP includes. */
58 #include "FreeRTOS_IP.h"
59 #include "FreeRTOS_Sockets.h"
60 #include "FreeRTOS_IP_Private.h"
61 
62 #include "Zynq/x_emacpsif.h"
63 #include "Zynq/x_topology.h"
64 #include "xstatus.h"
65 
66 #include "xparameters.h"
67 #include "xparameters_ps.h"
68 #include "xil_exception.h"
69 #include "xil_mmu.h"
70 
71 #include "uncached_memory.h"
72 
73 /* Reserve 1 MB of memory. */
74 #define uncMEMORY_SIZE         0x100000uL
75 
76 /* Make sure that each pointer has an alignment of 4 KB. */
77 #define uncALIGNMENT_SIZE      0x1000uL
78 
79 #define DDR_MEMORY_END         ( XPAR_PS7_DDR_0_S_AXI_HIGHADDR + 1 )
80 
81 #define uncMEMORY_ATTRIBUTE    0x1C02
82 
83 static void vInitialiseUncachedMemory( void );
84 
85 static uint8_t * pucHeadOfMemory;
86 static uint32_t ulMemorySize;
87 static uint8_t * pucStartOfMemory = NULL;
88 
89 /* The linker file defines some pseudo variables. '_end' is one of them.
90  * It is located at the first free byte in RAM. */
91 extern u8 _end;
92 
93 /*-----------------------------------------------------------*/
94 
ucIsCachedMemory(const uint8_t * pucBuffer)95 uint8_t ucIsCachedMemory( const uint8_t * pucBuffer )
96 {
97     uint8_t ucReturn;
98 
99     if( ( pucStartOfMemory != NULL ) &&
100         ( pucBuffer >= pucStartOfMemory ) &&
101         ( pucBuffer < ( pucStartOfMemory + uncMEMORY_SIZE ) ) )
102     {
103         ucReturn = pdFALSE;
104     }
105     else
106     {
107         ucReturn = pdTRUE;
108     }
109 
110     return ucReturn;
111 }
112 /*-----------------------------------------------------------*/
113 
pucGetUncachedMemory(uint32_t ulSize)114 uint8_t * pucGetUncachedMemory( uint32_t ulSize )
115 {
116     uint8_t * pucReturn;
117     uint32_t ulSkipSize;
118 
119     if( pucStartOfMemory == NULL )
120     {
121         vInitialiseUncachedMemory();
122     }
123 
124     if( ( pucStartOfMemory == NULL ) || ( ulSize > ulMemorySize ) )
125     {
126         pucReturn = NULL;
127     }
128     else
129     {
130         pucReturn = pucHeadOfMemory;
131         /* Make sure that the next pointer return will have a good alignment. */
132         ulSkipSize = ( ulSize + uncALIGNMENT_SIZE ) & ~( uncALIGNMENT_SIZE - 1uL );
133         pucHeadOfMemory += ulSkipSize;
134         ulMemorySize -= ulSkipSize;
135     }
136 
137     return pucReturn;
138 }
139 /*-----------------------------------------------------------*/
140 
vInitialiseUncachedMemory()141 static void vInitialiseUncachedMemory()
142 {
143     /* At the end of program's space... */
144     pucStartOfMemory = ( uint8_t * ) &( _end );
145 
146     /* Align the start address to 1 MB boundary. */
147     pucStartOfMemory = ( uint8_t * ) ( ( ( uint32_t ) pucStartOfMemory + uncMEMORY_SIZE ) & ( ~( uncMEMORY_SIZE - 1 ) ) );
148 
149     if( ( ( u32 ) pucStartOfMemory ) + uncMEMORY_SIZE > DDR_MEMORY_END )
150     {
151         FreeRTOS_printf( ( "vInitialiseUncachedMemory: Can not allocate uncached memory\n" ) );
152     }
153     else
154     {
155         /* Some objects want to be stored in uncached memory. Hence the 1 MB
156          * address range that starts after "_end" is made uncached by setting
157          * appropriate attributes in the translation table. */
158         Xil_SetTlbAttributes( ( uint32_t ) pucStartOfMemory, uncMEMORY_ATTRIBUTE );
159 
160         /* For experiments in the SDIO driver, make the remaining uncached memory
161          * public */
162         pucHeadOfMemory = pucStartOfMemory;
163         ulMemorySize = uncMEMORY_SIZE;
164         memset( pucStartOfMemory, '\0', uncMEMORY_SIZE );
165     }
166 }
167