summaryrefslogtreecommitdiff
path: root/drivers/scsi/esp_scsi.c
diff options
context:
space:
mode:
authorFinn Thain <fthain@telegraphics.com.au>2018-10-16 08:31:25 +0300
committerMartin K. Petersen <martin.petersen@oracle.com>2018-10-18 04:38:20 +0300
commit53dce332db507a2bd9797adc938fa293d1f1acc6 (patch)
treeb8eef76f487785808d03ad882d87b0c8e196bfd7 /drivers/scsi/esp_scsi.c
parent8bca2143335116af838305440d94539367382555 (diff)
downloadlinux-53dce332db507a2bd9797adc938fa293d1f1acc6.tar.xz
scsi: esp_scsi: De-duplicate PIO routines
As a temporary measure, the code to implement PIO transfers was duplicated in zorro_esp and mac_esp. Now that it has stabilized move the common code into the core driver but don't build it unless needed. This replaces the inline assembler with more portable writesb() calls. Optimizing the m68k writesb() implementation is a separate patch. [mkp: applied by hand] Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Stan Johnson <userm57@yahoo.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/esp_scsi.c')
-rw-r--r--drivers/scsi/esp_scsi.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/scsi/esp_scsi.c b/drivers/scsi/esp_scsi.c
index 752857dc6437..a167f70e76c3 100644
--- a/drivers/scsi/esp_scsi.c
+++ b/drivers/scsi/esp_scsi.c
@@ -2782,3 +2782,131 @@ MODULE_PARM_DESC(esp_debug,
module_init(esp_init);
module_exit(esp_exit);
+
+#ifdef CONFIG_SCSI_ESP_PIO
+static inline unsigned int esp_wait_for_fifo(struct esp *esp)
+{
+ int i = 500000;
+
+ do {
+ unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
+
+ if (fbytes)
+ return fbytes;
+
+ udelay(2);
+ } while (--i);
+
+ shost_printk(KERN_ERR, esp->host, "FIFO is empty. sreg [%02x]\n",
+ esp_read8(ESP_STATUS));
+ return 0;
+}
+
+static inline int esp_wait_for_intr(struct esp *esp)
+{
+ int i = 500000;
+
+ do {
+ esp->sreg = esp_read8(ESP_STATUS);
+ if (esp->sreg & ESP_STAT_INTR)
+ return 0;
+
+ udelay(2);
+ } while (--i);
+
+ shost_printk(KERN_ERR, esp->host, "IRQ timeout. sreg [%02x]\n",
+ esp->sreg);
+ return 1;
+}
+
+#define ESP_FIFO_SIZE 16
+
+void esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
+ u32 dma_count, int write, u8 cmd)
+{
+ u8 phase = esp->sreg & ESP_STAT_PMASK;
+
+ cmd &= ~ESP_CMD_DMA;
+ esp->send_cmd_error = 0;
+
+ if (write) {
+ u8 *dst = (u8 *)addr;
+ u8 mask = ~(phase == ESP_MIP ? ESP_INTR_FDONE : ESP_INTR_BSERV);
+
+ scsi_esp_cmd(esp, cmd);
+
+ while (1) {
+ if (!esp_wait_for_fifo(esp))
+ break;
+
+ *dst++ = esp_read8(ESP_FDATA);
+ --esp_count;
+
+ if (!esp_count)
+ break;
+
+ if (esp_wait_for_intr(esp)) {
+ esp->send_cmd_error = 1;
+ break;
+ }
+
+ if ((esp->sreg & ESP_STAT_PMASK) != phase)
+ break;
+
+ esp->ireg = esp_read8(ESP_INTRPT);
+ if (esp->ireg & mask) {
+ esp->send_cmd_error = 1;
+ break;
+ }
+
+ if (phase == ESP_MIP)
+ scsi_esp_cmd(esp, ESP_CMD_MOK);
+
+ scsi_esp_cmd(esp, ESP_CMD_TI);
+ }
+ } else {
+ unsigned int n = ESP_FIFO_SIZE;
+ u8 *src = (u8 *)addr;
+
+ scsi_esp_cmd(esp, ESP_CMD_FLUSH);
+
+ if (n > esp_count)
+ n = esp_count;
+ writesb(esp->fifo_reg, src, n);
+ src += n;
+ esp_count -= n;
+
+ scsi_esp_cmd(esp, cmd);
+
+ while (esp_count) {
+ if (esp_wait_for_intr(esp)) {
+ esp->send_cmd_error = 1;
+ break;
+ }
+
+ if ((esp->sreg & ESP_STAT_PMASK) != phase)
+ break;
+
+ esp->ireg = esp_read8(ESP_INTRPT);
+ if (esp->ireg & ~ESP_INTR_BSERV) {
+ esp->send_cmd_error = 1;
+ break;
+ }
+
+ n = ESP_FIFO_SIZE -
+ (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
+
+ if (n > esp_count)
+ n = esp_count;
+ writesb(esp->fifo_reg, src, n);
+ src += n;
+ esp_count -= n;
+
+ scsi_esp_cmd(esp, ESP_CMD_TI);
+ }
+ }
+
+ esp->send_cmd_residual = esp_count;
+}
+EXPORT_SYMBOL(esp_send_pio_cmd);
+#endif