File: /usr/src/linux/drivers/scsi/sun3x_esp.c

1     /* sun3x_esp.c:  EnhancedScsiProcessor Sun3x SCSI driver code.
2      *
3      * (C) 1999 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
4      *
5      * Based on David S. Miller's esp driver
6      */
7     
8     #include <linux/kernel.h>
9     #include <linux/types.h>
10     #include <linux/string.h>
11     #include <linux/slab.h>
12     #include <linux/blk.h>
13     #include <linux/proc_fs.h>
14     #include <linux/stat.h>
15     #include <linux/delay.h>
16     
17     #include "scsi.h"
18     #include "hosts.h"
19     #include "NCR53C9x.h"
20     
21     #include "sun3x_esp.h"
22     #include <asm/sun3x.h>
23     #include <asm/dvma.h>
24     
25     extern struct NCR_ESP *espchain;
26     
27     static void dma_barrier(struct NCR_ESP *esp);
28     static int  dma_bytes_sent(struct NCR_ESP *esp, int fifo_count);
29     static int  dma_can_transfer(struct NCR_ESP *esp, Scsi_Cmnd *sp);
30     static void dma_drain(struct NCR_ESP *esp);
31     static void dma_dump_state(struct NCR_ESP *esp);
32     static void dma_init_read(struct NCR_ESP *esp, __u32 vaddress, int length);
33     static void dma_init_write(struct NCR_ESP *esp, __u32 vaddress, int length);
34     static void dma_ints_off(struct NCR_ESP *esp);
35     static void dma_ints_on(struct NCR_ESP *esp);
36     static int  dma_irq_p(struct NCR_ESP *esp);
37     static void dma_poll(struct NCR_ESP *esp, unsigned char *vaddr);
38     static int  dma_ports_p(struct NCR_ESP *esp);
39     static void dma_reset(struct NCR_ESP *esp);
40     static void dma_setup(struct NCR_ESP *esp, __u32 addr, int count, int write);
41     static void dma_mmu_get_scsi_one (struct NCR_ESP *esp, Scsi_Cmnd *sp);
42     static void dma_mmu_get_scsi_sgl (struct NCR_ESP *esp, Scsi_Cmnd *sp);
43     static void dma_mmu_release_scsi_one (struct NCR_ESP *esp, Scsi_Cmnd *sp);
44     static void dma_mmu_release_scsi_sgl (struct NCR_ESP *esp, Scsi_Cmnd *sp);
45     static void dma_advance_sg (Scsi_Cmnd *sp);
46     
47     volatile unsigned char cmd_buffer[16];
48                                     /* This is where all commands are put
49                                      * before they are trasfered to the ESP chip
50                                      * via PIO.
51                                      */
52     
53     /* Detecting ESP chips on the machine.  This is the simple and easy
54      * version.
55      */
56     int sun3x_esp_detect(Scsi_Host_Template *tpnt)
57     {
58     	struct NCR_ESP *esp;
59     	struct ConfigDev *esp_dev;
60     
61     	esp_dev = 0;
62     	esp = esp_allocate(tpnt, (void *) esp_dev);
63     
64     	/* Do command transfer with DMA */
65     	esp->do_pio_cmds = 0;
66     
67     	/* Required functions */
68     	esp->dma_bytes_sent = &dma_bytes_sent;
69     	esp->dma_can_transfer = &dma_can_transfer;
70     	esp->dma_dump_state = &dma_dump_state;
71     	esp->dma_init_read = &dma_init_read;
72     	esp->dma_init_write = &dma_init_write;
73     	esp->dma_ints_off = &dma_ints_off;
74     	esp->dma_ints_on = &dma_ints_on;
75     	esp->dma_irq_p = &dma_irq_p;
76     	esp->dma_ports_p = &dma_ports_p;
77     	esp->dma_setup = &dma_setup;
78     
79     	/* Optional functions */
80     	esp->dma_barrier = &dma_barrier;
81     	esp->dma_drain = &dma_drain;
82     	esp->dma_irq_entry = &dma_ints_off;
83     	esp->dma_irq_exit = &dma_ints_on;
84     	esp->dma_led_on = 0;
85     	esp->dma_led_off = 0;
86     	esp->dma_poll = &dma_poll;
87     	esp->dma_reset = &dma_reset;
88     
89             /* virtual DMA functions */
90             esp->dma_mmu_get_scsi_one = &dma_mmu_get_scsi_one;
91             esp->dma_mmu_get_scsi_sgl = &dma_mmu_get_scsi_sgl;
92             esp->dma_mmu_release_scsi_one = &dma_mmu_release_scsi_one;
93             esp->dma_mmu_release_scsi_sgl = &dma_mmu_release_scsi_sgl;
94             esp->dma_advance_sg = &dma_advance_sg;
95     	    
96     	/* SCSI chip speed */
97     	esp->cfreq = 20000000;
98     	esp->eregs = (struct ESP_regs *)(SUN3X_ESP_BASE);
99     	esp->dregs = (void *)SUN3X_ESP_DMA;
100     
101     	esp->esp_command = (volatile unsigned char *)cmd_buffer;
102     	esp->esp_command_dvma = dvma_alloc(virt_to_phys(cmd_buffer), 
103     					   sizeof (cmd_buffer));
104     
105     	esp->irq = 2;
106     	if (request_irq(esp->irq, esp_intr, SA_INTERRUPT, 
107     			"SUN3X SCSI", NULL)) {
108     		esp_deallocate(esp);
109     		return 0;
110     	}
111     
112     	esp->scsi_id = 7;
113     	esp->diff = 0;
114     
115     	esp_initialize(esp);
116     
117     	printk("ESP: Total of %d ESP hosts found, %d actually in use.\n", nesps,
118     	       esps_in_use);
119     	esps_running = esps_in_use;
120     	return esps_in_use;
121     }
122     
123     static void dma_barrier(struct NCR_ESP *esp)
124     {
125     	struct sparc_dma_registers *dregs =
126     		(struct sparc_dma_registers *) esp->dregs;
127     
128     	while(dregs->cond_reg & DMA_PEND_READ)
129     		udelay(1);
130     	dregs->cond_reg &= ~(DMA_ENABLE);
131     }
132     
133     /* This uses various DMA csr fields and the fifo flags count value to
134      * determine how many bytes were successfully sent/received by the ESP.
135      */
136     static int dma_bytes_sent(struct NCR_ESP *esp, int fifo_count)
137     {
138     	struct sparc_dma_registers *dregs = 
139     		(struct sparc_dma_registers *) esp->dregs;
140     
141     	int rval = dregs->st_addr - esp->esp_command_dvma;
142     
143     	return rval - fifo_count;
144     }
145     
146     static int dma_can_transfer(struct NCR_ESP *esp, Scsi_Cmnd *sp)
147     {
148     	__u32 base, end, sz;
149     
150     	base = ((__u32)sp->SCp.ptr);
151     	base &= (0x1000000 - 1);
152     	end = (base + sp->SCp.this_residual);
153     	if(end > 0x1000000)
154     		end = 0x1000000;
155     	sz = (end - base);
156     	return sz;
157     }
158     
159     static void dma_drain(struct NCR_ESP *esp)
160     {
161     	struct sparc_dma_registers *dregs =
162     		(struct sparc_dma_registers *) esp->dregs;
163     
164     	if(dregs->cond_reg & DMA_FIFO_ISDRAIN) {
165     		dregs->cond_reg |= DMA_FIFO_STDRAIN;
166     		while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
167     			udelay(1);
168     	}
169     }
170     
171     static void dma_dump_state(struct NCR_ESP *esp)
172     {
173     	struct sparc_dma_registers *dregs =
174     		(struct sparc_dma_registers *) esp->dregs;
175     
176     	ESPLOG(("esp%d: dma -- cond_reg<%08lx> addr<%p>\n",
177     		esp->esp_id, dregs->cond_reg, dregs->st_addr));
178     }
179     
180     static void dma_init_read(struct NCR_ESP *esp, __u32 vaddress, int length)
181     {
182     	struct sparc_dma_registers *dregs = 
183     		(struct sparc_dma_registers *) esp->dregs;
184     
185     	dregs->cond_reg |= (DMA_ST_WRITE | DMA_ENABLE);
186     	dregs->st_addr = vaddress;
187     }
188     
189     static void dma_init_write(struct NCR_ESP *esp, __u32 vaddress, int length)
190     {
191     	struct sparc_dma_registers *dregs = 
192     		(struct sparc_dma_registers *) esp->dregs;
193     
194     	/* Set up the DMA counters */
195     	dregs->cond_reg = ((dregs->cond_reg & ~(DMA_ST_WRITE)) | DMA_ENABLE);
196     	dregs->st_addr = vaddress;
197     }
198     
199     static void dma_ints_off(struct NCR_ESP *esp)
200     {
201     	DMA_INTSOFF((struct sparc_dma_registers *) esp->dregs);
202     }
203     
204     static void dma_ints_on(struct NCR_ESP *esp)
205     {
206     	DMA_INTSON((struct sparc_dma_registers *) esp->dregs);
207     }
208     
209     static int dma_irq_p(struct NCR_ESP *esp)
210     {
211     	return DMA_IRQ_P((struct sparc_dma_registers *) esp->dregs);
212     }
213     
214     static void dma_poll(struct NCR_ESP *esp, unsigned char *vaddr)
215     {
216     	dma_drain(esp);
217     
218     	/* Wait till the first bits settle. */
219     	while(vaddr[0] == 0xff)
220     		udelay(1);
221     }	
222     
223     static int dma_ports_p(struct NCR_ESP *esp)
224     {
225     	return (((struct sparc_dma_registers *) esp->dregs)->cond_reg 
226     			& DMA_INT_ENAB);
227     }
228     
229     /* Resetting various pieces of the ESP scsi driver chipset/buses. */
230     static void dma_reset(struct NCR_ESP *esp)
231     {
232     	struct sparc_dma_registers *dregs =
233     		(struct sparc_dma_registers *)esp->dregs;
234     
235     	/* Punt the DVMA into a known state. */
236     	dregs->cond_reg |= DMA_RST_SCSI;
237     	dregs->cond_reg &= ~(DMA_RST_SCSI);
238     	DMA_INTSON(dregs);
239     }
240     
241     static void dma_setup(struct NCR_ESP *esp, __u32 addr, int count, int write)
242     {
243     	struct sparc_dma_registers *dregs = 
244     		(struct sparc_dma_registers *) esp->dregs;
245     	unsigned long nreg = dregs->cond_reg;
246     
247     	if(write)
248     		nreg |= DMA_ST_WRITE;
249     	else
250     		nreg &= ~(DMA_ST_WRITE);
251     	nreg |= DMA_ENABLE;
252     	dregs->cond_reg = nreg;
253     	dregs->st_addr = addr;
254     }
255     
256     static void dma_mmu_get_scsi_one (struct NCR_ESP *esp, Scsi_Cmnd *sp)
257     {
258         sp->SCp.have_data_in = dvma_alloc(virt_to_phys(sp->SCp.buffer),
259     				       sp->SCp.this_residual);
260         sp->SCp.ptr = (char *)((unsigned long)sp->SCp.have_data_in);
261     }
262     
263     static void dma_mmu_get_scsi_sgl (struct NCR_ESP *esp, Scsi_Cmnd *sp)
264     {
265         int sz = sp->SCp.buffers_residual;
266         struct mmu_sglist *sg = (struct mmu_sglist *) sp->SCp.buffer;
267     
268         while (sz >= 0) {
269             sg[sz].dvma_addr = dvma_alloc(virt_to_phys(sg[sz].addr), sg[sz].len);
270             sz--;
271         }
272         sp->SCp.ptr=(char *)((unsigned long)sp->SCp.buffer->dvma_address);
273     }
274     
275     static void dma_mmu_release_scsi_one (struct NCR_ESP *esp, Scsi_Cmnd *sp)
276     {
277         dvma_free(sp->SCp.have_data_in, sp->request_bufflen);
278     }
279     
280     static void dma_mmu_release_scsi_sgl (struct NCR_ESP *esp, Scsi_Cmnd *sp)
281     {
282         int sz = sp->use_sg - 1;
283         struct mmu_sglist *sg = (struct mmu_sglist *)sp->buffer;
284                             
285         while(sz >= 0) {
286             dvma_free(sg[sz].dvma_addr,sg[sz].len);
287             sz--;
288         }
289     }
290     
291     static void dma_advance_sg (Scsi_Cmnd *sp)
292     {
293         sp->SCp.ptr = (char *)((unsigned long)sp->SCp.buffer->dvma_address);
294     }
295     
296     static Scsi_Host_Template driver_template = SCSI_SUN3X_ESP;
297     
298     #include "scsi_module.c"
299