From e8bc1621c6882766815d2a46f5c2ae88c977bfa4 Mon Sep 17 00:00:00 2001
From: Mayuresh Chitale <mchitale@ventanamicro.com>
Date: Thu, 7 Sep 2023 17:19:46 +0530
Subject: [PATCH] lib: utils/serial: Add shared regions for serial drivers

The serial driver regions used by OpenSBI should be marked as a shared
read-write regions between M-mode and SU-mode as those are accessed
by earlycon and the corresponding tty serial drivers running in 'S' mode.
When the smepmp extension is enabled, PMP entries for these shared regions
will get programmed.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 lib/utils/serial/cadence-uart.c    | 6 +++++-
 lib/utils/serial/fdt_serial_htif.c | 9 +++++++++
 lib/utils/serial/uart8250.c        | 7 ++++++-
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/lib/utils/serial/cadence-uart.c b/lib/utils/serial/cadence-uart.c
index 8a2b6ba7..30fbb95f 100644
--- a/lib/utils/serial/cadence-uart.c
+++ b/lib/utils/serial/cadence-uart.c
@@ -6,6 +6,8 @@
  * Author: Jun Liang Tan <junliang.tan@linux.starfivetech.com>
  */
 
+#include <sbi/sbi_domain.h>
+#include <sbi/riscv_asm.h>
 #include <sbi/riscv_io.h>
 #include <sbi/sbi_console.h>
 #include <sbi_utils/serial/cadence-uart.h>
@@ -124,5 +126,7 @@ int cadence_uart_init(unsigned long base, u32 in_freq, u32 baudrate)
 
 	sbi_console_set_device(&cadence_console);
 
-	return 0;
+	return sbi_domain_root_add_memrange(base, PAGE_SIZE, PAGE_SIZE,
+					    (SBI_DOMAIN_MEMREGION_MMIO |
+					    SBI_DOMAIN_MEMREGION_SHARED_SURW_MRW));
 }
diff --git a/lib/utils/serial/fdt_serial_htif.c b/lib/utils/serial/fdt_serial_htif.c
index 61f66d68..7d88e7a1 100644
--- a/lib/utils/serial/fdt_serial_htif.c
+++ b/lib/utils/serial/fdt_serial_htif.c
@@ -7,6 +7,8 @@
  *   Anup Patel <anup.patel@wdc.com>
  */
 
+#include <sbi/riscv_asm.h>
+#include <sbi/sbi_domain.h>
 #include <sbi_utils/fdt/fdt_helper.h>
 #include <sbi_utils/serial/fdt_serial.h>
 #include <sbi_utils/sys/htif.h>
@@ -19,6 +21,7 @@ static const struct fdt_match serial_htif_match[] = {
 static int serial_htif_init(void *fdt, int nodeoff,
 			    const struct fdt_match *match)
 {
+	int rc;
 	bool custom = false;
 	uint64_t fromhost_addr = 0, tohost_addr = 0;
 
@@ -29,6 +32,12 @@ static int serial_htif_init(void *fdt, int nodeoff,
 
 	fdt_get_node_addr_size(fdt, nodeoff, 1, &tohost_addr, NULL);
 
+	rc = sbi_domain_root_add_memrange(fromhost_addr, PAGE_SIZE, PAGE_SIZE,
+					  (SBI_DOMAIN_MEMREGION_MMIO |
+					   SBI_DOMAIN_MEMREGION_SHARED_SURW_MRW));
+	if (rc)
+		return rc;
+
 	return htif_serial_init(custom, fromhost_addr, tohost_addr);
 }
 
diff --git a/lib/utils/serial/uart8250.c b/lib/utils/serial/uart8250.c
index 99bf1bf7..4d158d3b 100644
--- a/lib/utils/serial/uart8250.c
+++ b/lib/utils/serial/uart8250.c
@@ -7,8 +7,10 @@
  *   Anup Patel <anup.patel@wdc.com>
  */
 
+#include <sbi/riscv_asm.h>
 #include <sbi/riscv_io.h>
 #include <sbi/sbi_console.h>
+#include <sbi/sbi_domain.h>
 #include <sbi_utils/serial/uart8250.h>
 
 /* clang-format off */
@@ -133,5 +135,8 @@ int uart8250_init(unsigned long base, u32 in_freq, u32 baudrate, u32 reg_shift,
 
 	sbi_console_set_device(&uart8250_console);
 
-	return 0;
+	return sbi_domain_root_add_memrange(base + reg_offset, PAGE_SIZE,
+					    PAGE_SIZE,
+					    (SBI_DOMAIN_MEMREGION_MMIO |
+					    SBI_DOMAIN_MEMREGION_SHARED_SURW_MRW));
 }