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Diffstat (limited to 'src/soc/intel/skylake/iobp.c')
-rw-r--r--src/soc/intel/skylake/iobp.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/src/soc/intel/skylake/iobp.c b/src/soc/intel/skylake/iobp.c
new file mode 100644
index 0000000000..870f6af597
--- /dev/null
+++ b/src/soc/intel/skylake/iobp.c
@@ -0,0 +1,152 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <console/console.h>
+#include <delay.h>
+#include <arch/io.h>
+#include <soc/iobp.h>
+#include <soc/rcba.h>
+
+#define IOBP_RETRY 1000
+
+static inline int iobp_poll(void)
+{
+ unsigned try;
+
+ for (try = IOBP_RETRY; try > 0; try--) {
+ u16 status = RCBA16(IOBPS);
+ if ((status & IOBPS_READY) == 0)
+ return 1;
+ udelay(10);
+ }
+
+ printk(BIOS_ERR, "IOBP: timeout waiting for transaction to complete\n");
+ return 0;
+}
+
+u32 pch_iobp_read(u32 address)
+{
+ u16 status;
+
+ if (!iobp_poll())
+ return 0;
+
+ /* Set the address */
+ RCBA32(IOBPIRI) = address;
+
+ /* READ OPCODE */
+ status = RCBA16(IOBPS);
+ status &= ~IOBPS_MASK;
+ status |= IOBPS_READ;
+ RCBA16(IOBPS) = status;
+
+ /* Undocumented magic */
+ RCBA16(IOBPU) = IOBPU_MAGIC;
+
+ /* Set ready bit */
+ status = RCBA16(IOBPS);
+ status |= IOBPS_READY;
+ RCBA16(IOBPS) = status;
+
+ if (!iobp_poll())
+ return 0;
+
+ /* Check for successful transaction */
+ status = RCBA16(IOBPS);
+ if (status & IOBPS_TX_MASK) {
+ printk(BIOS_ERR, "IOBP: read 0x%08x failed\n", address);
+ return 0;
+ }
+
+ /* Read IOBP data */
+ return RCBA32(IOBPD);
+}
+
+void pch_iobp_write(u32 address, u32 data)
+{
+ u16 status;
+
+ if (!iobp_poll())
+ return;
+
+ /* Set the address */
+ RCBA32(IOBPIRI) = address;
+
+ /* WRITE OPCODE */
+ status = RCBA16(IOBPS);
+ status &= ~IOBPS_MASK;
+ status |= IOBPS_WRITE;
+ RCBA16(IOBPS) = status;
+
+ RCBA32(IOBPD) = data;
+
+ /* Undocumented magic */
+ RCBA16(IOBPU) = IOBPU_MAGIC;
+
+ /* Set ready bit */
+ status = RCBA16(IOBPS);
+ status |= IOBPS_READY;
+ RCBA16(IOBPS) = status;
+
+ if (!iobp_poll())
+ return;
+
+ /* Check for successful transaction */
+ status = RCBA16(IOBPS);
+ if (status & IOBPS_TX_MASK)
+ printk(BIOS_ERR, "IOBP: write 0x%08x failed\n", address);
+}
+
+void pch_iobp_update(u32 address, u32 andvalue, u32 orvalue)
+{
+ u32 data = pch_iobp_read(address);
+
+ /* Update the data */
+ data &= andvalue;
+ data |= orvalue;
+
+ pch_iobp_write(address, data);
+}
+
+void pch_iobp_exec(u32 addr, u16 op_code, u8 route_id, u32 *data, u8 *resp)
+{
+ if (!data || !resp)
+ return;
+
+ *resp = -1;
+ if (!iobp_poll())
+ return;
+
+ /* RCBA2330[31:0] = Address */
+ RCBA32(IOBPIRI) = addr;
+ /* RCBA2338[15:8] = opcode */
+ RCBA16(IOBPS) = (RCBA16(IOBPS) & 0x00ff) | op_code;
+ /* RCBA233A[15:8] = 0xf0 RCBA233A[7:0] = Route ID */
+ RCBA16(IOBPU) = IOBPU_MAGIC | route_id;
+
+ RCBA32(IOBPD) = *data;
+ /* Set RCBA2338[0] to trigger IOBP transaction*/
+ RCBA16(IOBPS) = RCBA16(IOBPS) | 0x1;
+
+ if (!iobp_poll())
+ return;
+
+ *resp = (RCBA16(IOBPS) & IOBPS_TX_MASK) >> 1;
+ *data = RCBA32(IOBPD);
+}