diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e0427ce4a53..211d408e3f7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -113,9 +113,6 @@ jobs:
   esp32s2-hal:
     runs-on: ubuntu-latest
 
-    env:
-      RUSTFLAGS: '--cfg target_has_atomic="8" --cfg target_has_atomic="16" --cfg target_has_atomic="32" --cfg target_has_atomic="ptr"'
-
     steps:
       - uses: actions/checkout@v2
       - uses: esp-rs/xtensa-toolchain@v1.5
diff --git a/esp-hal-common/src/clocks_ll/esp32.rs b/esp-hal-common/src/clock/clocks_ll/esp32.rs
similarity index 100%
rename from esp-hal-common/src/clocks_ll/esp32.rs
rename to esp-hal-common/src/clock/clocks_ll/esp32.rs
diff --git a/esp-hal-common/src/clocks_ll/esp32c2.rs b/esp-hal-common/src/clock/clocks_ll/esp32c2.rs
similarity index 97%
rename from esp-hal-common/src/clocks_ll/esp32c2.rs
rename to esp-hal-common/src/clock/clocks_ll/esp32c2.rs
index bbe52641416..2c6c4462ed4 100644
--- a/esp-hal-common/src/clocks_ll/esp32c2.rs
+++ b/esp-hal-common/src/clock/clocks_ll/esp32c2.rs
@@ -4,9 +4,13 @@ use crate::{
     clock::{ApbClock, Clock, CpuClock, PllClock, XtalClock},
     regi2c_write,
     regi2c_write_mask,
-    rom::{ets_update_cpu_frequency, regi2c_ctrl_write_reg, regi2c_ctrl_write_reg_mask},
+    rom::{rom_i2c_writeReg, rom_i2c_writeReg_Mask},
 };
 
+extern "C" {
+    fn ets_update_cpu_frequency(ticks_per_us: u32);
+}
+
 const I2C_BBPLL: u32 = 0x66;
 const I2C_BBPLL_HOSTID: u32 = 0;
 
diff --git a/esp-hal-common/src/clocks_ll/esp32c3.rs b/esp-hal-common/src/clock/clocks_ll/esp32c3.rs
similarity index 98%
rename from esp-hal-common/src/clocks_ll/esp32c3.rs
rename to esp-hal-common/src/clock/clocks_ll/esp32c3.rs
index 4e2cff076bc..6afb6d33666 100644
--- a/esp-hal-common/src/clocks_ll/esp32c3.rs
+++ b/esp-hal-common/src/clock/clocks_ll/esp32c3.rs
@@ -4,9 +4,13 @@ use crate::{
     clock::{ApbClock, Clock, CpuClock, PllClock, XtalClock},
     regi2c_write,
     regi2c_write_mask,
-    rom::{ets_update_cpu_frequency, regi2c_ctrl_write_reg, regi2c_ctrl_write_reg_mask},
+    rom::{rom_i2c_writeReg, rom_i2c_writeReg_Mask},
 };
 
+extern "C" {
+    fn ets_update_cpu_frequency(ticks_per_us: u32);
+}
+
 const I2C_BBPLL: u32 = 0x66;
 const I2C_BBPLL_HOSTID: u32 = 0;
 
diff --git a/esp-hal-common/src/clocks_ll/esp32s2.rs b/esp-hal-common/src/clock/clocks_ll/esp32s2.rs
similarity index 100%
rename from esp-hal-common/src/clocks_ll/esp32s2.rs
rename to esp-hal-common/src/clock/clocks_ll/esp32s2.rs
diff --git a/esp-hal-common/src/clocks_ll/esp32s3.rs b/esp-hal-common/src/clock/clocks_ll/esp32s3.rs
similarity index 100%
rename from esp-hal-common/src/clocks_ll/esp32s3.rs
rename to esp-hal-common/src/clock/clocks_ll/esp32s3.rs
diff --git a/esp-hal-common/src/clock.rs b/esp-hal-common/src/clock/mod.rs
similarity index 100%
rename from esp-hal-common/src/clock.rs
rename to esp-hal-common/src/clock/mod.rs
diff --git a/esp-hal-common/src/rom.rs b/esp-hal-common/src/rom.rs
index 6d52f273b52..f4549cdbc8c 100644
--- a/esp-hal-common/src/rom.rs
+++ b/esp-hal-common/src/rom.rs
@@ -1,147 +1,43 @@
 pub use paste::paste;
 
-/// Pauses execution for us microseconds
-#[inline(always)]
-pub unsafe fn esp_rom_delay_us(us: u32) {
-    #[cfg(esp32)]
-    const ESP_ROM_DELAY_US: u32 = 0x4000_8534;
-    #[cfg(esp32c2)]
-    const ESP_ROM_DELAY_US: u32 = 0x4000_0044;
-    #[cfg(esp32c3)]
-    const ESP_ROM_DELAY_US: u32 = 0x4000_0050;
-    #[cfg(esp32s2)]
-    const ESP_ROM_DELAY_US: u32 = 0x4000_d888;
-    #[cfg(esp32s3)]
-    const ESP_ROM_DELAY_US: u32 = 0x4000_0600;
+#[allow(unused)]
+extern "C" {
+    pub(crate) fn rom_i2c_writeReg(block: u32, block_hostid: u32, reg_add: u32, indata: u32);
 
-    // cast to usize is just needed because of the way we run clippy in CI
-    let fn_esp_rom_delay_us: fn(us: u32) = core::mem::transmute(ESP_ROM_DELAY_US as usize);
-
-    fn_esp_rom_delay_us(us);
-}
-
-#[inline(always)]
-/// Set the real CPU ticks per us to the ets, so that ets_delay_us
-/// will be accurate. Call this function when CPU frequency is changed.
-pub unsafe fn ets_update_cpu_frequency(ticks_per_us: u32) {
-    #[cfg(esp32)]
-    const ETS_UPDATE_CPU_FREQUENCY: u32 = 0x4000_8550;
-    #[cfg(esp32c2)]
-    const ETS_UPDATE_CPU_FREQUENCY: u32 = 0x4000_0774;
-    #[cfg(esp32c3)]
-    const ETS_UPDATE_CPU_FREQUENCY: u32 = 0x4000_0588;
-    #[cfg(esp32s2)]
-    const ETS_UPDATE_CPU_FREQUENCY: u32 = 0x4000_d8a4;
-    #[cfg(esp32s3)]
-    const ETS_UPDATE_CPU_FREQUENCY: u32 = 0x4004_3164;
-
-    // cast to usize is just needed because of the way we run clippy in CI
-    let rom_ets_update_cpu_frequency: fn(ticks_per_us: u32) =
-        core::mem::transmute(ETS_UPDATE_CPU_FREQUENCY as usize);
-
-    rom_ets_update_cpu_frequency(ticks_per_us);
-}
-
-#[inline(always)]
-pub unsafe fn regi2c_ctrl_write_reg(block: u32, block_hostid: u32, reg_add: u32, indata: u32) {
-    #[cfg(esp32)]
-    const ROM_I2C_WRITEREG: u32 = 0x4000_41a4;
-    #[cfg(esp32c2)]
-    const ROM_I2C_WRITEREG: u32 = 0x4000_22f4;
-    #[cfg(esp32c3)]
-    const ROM_I2C_WRITEREG: u32 = 0x4000_195c;
-    #[cfg(esp32s2)]
-    const ROM_I2C_WRITEREG: u32 = 0x4000_a9a8;
-    #[cfg(esp32s3)]
-    const ROM_I2C_WRITEREG: u32 = 0x4000_5d60;
-
-    // cast to usize is just needed because of the way we run clippy in CI
-    let i2c_write_reg_raw: fn(block: u32, block_hostid: u32, reg_add: u32, indata: u32) -> i32 =
-        core::mem::transmute(ROM_I2C_WRITEREG as usize);
-
-    i2c_write_reg_raw(block, block_hostid, reg_add, indata);
+    pub(crate) fn rom_i2c_writeReg_Mask(
+        block: u32,
+        block_hostid: u32,
+        reg_add: u32,
+        reg_add_msb: u32,
+        reg_add_lsb: u32,
+        indata: u32,
+    );
 }
 
 #[macro_export]
 macro_rules! regi2c_write {
     ( $block: ident, $reg_add: ident, $indata: expr ) => {
         paste! {
-            regi2c_ctrl_write_reg($block,
+            rom_i2c_writeReg($block,
                 [<$block _HOSTID>],
                 $reg_add,
-                $indata);
+                $indata
+            );
         }
     };
 }
 
-#[inline(always)]
-pub unsafe fn regi2c_ctrl_write_reg_mask(
-    block: u32,
-    block_hostid: u32,
-    reg_add: u32,
-    reg_add_msb: u32,
-    reg_add_lsb: u32,
-    indata: u32,
-) {
-    #[cfg(esp32)]
-    const ROM_I2C_WRITEREG_MASK: u32 = 0x4000_41fc;
-    #[cfg(esp32c2)]
-    const ROM_I2C_WRITEREG_MASK: u32 = 0x4000_22fc;
-    #[cfg(esp32c3)]
-    const ROM_I2C_WRITEREG_MASK: u32 = 0x4000_1960;
-    #[cfg(esp32s2)]
-    const ROM_I2C_WRITEREG_MASK: u32 = 0x4000_aa00;
-    #[cfg(esp32s3)]
-    const ROM_I2C_WRITEREG_MASK: u32 = 0x4000_5d6c;
-
-    // cast to usize is just needed because of the way we run clippy in CI
-    let i2c_write_reg_mask_raw: fn(
-        block: u32,
-        block_hostid: u32,
-        reg_add: u32,
-        reg_add_msb: u32,
-        reg_add_lsb: u32,
-        indata: u32,
-    ) -> i32 = core::mem::transmute(ROM_I2C_WRITEREG_MASK as usize);
-
-    i2c_write_reg_mask_raw(
-        block,
-        block_hostid,
-        reg_add,
-        reg_add_msb,
-        reg_add_lsb,
-        indata,
-    );
-}
-
 #[macro_export]
 macro_rules! regi2c_write_mask {
     ( $block: ident, $reg_add: ident, $indata: expr ) => {
         paste! {
-            regi2c_ctrl_write_reg_mask($block,
+            rom_i2c_writeReg_Mask($block,
                 [<$block _HOSTID>],
                 $reg_add,
                 [<$reg_add _MSB>],
                 [<$reg_add _LSB>],
-                $indata);
+                $indata
+            );
         }
     };
 }
-
-/// Determine the reason that the specified CPU reset
-pub unsafe fn rtc_get_reset_reason(cpu_num: u32) -> u32 {
-    #[cfg(esp32)]
-    const RTC_GET_RESET_REASON: u32 = 0x4000_81d4;
-    #[cfg(esp32c2)]
-    const RTC_GET_RESET_REASON: u32 = 0x4000_0018;
-    #[cfg(esp32c3)]
-    const RTC_GET_RESET_REASON: u32 = 0x4000_0018;
-    #[cfg(esp32s2)]
-    const RTC_GET_RESET_REASON: u32 = 0x4000_ff58;
-    #[cfg(esp32s3)]
-    const RTC_GET_RESET_REASON: u32 = 0x4000_057c;
-
-    let get_reason: fn(u32) -> u32 = core::mem::transmute(RTC_GET_RESET_REASON as usize);
-
-    get_reason(cpu_num)
-}
diff --git a/esp-hal-common/src/rtc_cntl/mod.rs b/esp-hal-common/src/rtc_cntl/mod.rs
index 7a610efc486..69ff5e86060 100644
--- a/esp-hal-common/src/rtc_cntl/mod.rs
+++ b/esp-hal-common/src/rtc_cntl/mod.rs
@@ -8,7 +8,6 @@ use crate::{
     clock::{Clock, XtalClock},
     peripheral::{Peripheral, PeripheralRef},
     peripherals::{RTC_CNTL, TIMG0},
-    rom::esp_rom_delay_us,
     Cpu,
 };
 
@@ -19,6 +18,12 @@ use crate::{
 #[cfg_attr(esp32s3, path = "rtc/esp32s3.rs")]
 mod rtc;
 
+extern "C" {
+    fn ets_delay_us(us: u32);
+
+    fn rtc_get_reset_reason(cpu_num: u32) -> u32;
+}
+
 #[allow(unused)]
 #[derive(Debug, Clone, Copy)]
 /// RTC SLOW_CLK frequency values
@@ -137,7 +142,7 @@ impl RtcClock {
             rtc_cntl.clk_conf.modify(|_, w| w.enb_ck8m().clear_bit());
             unsafe {
                 rtc_cntl.timer1.modify(|_, w| w.ck8m_wait().bits(5));
-                esp_rom_delay_us(50);
+                ets_delay_us(50);
             }
         } else {
             rtc_cntl.clk_conf.modify(|_, w| w.enb_ck8m().set_bit());
@@ -222,7 +227,7 @@ impl RtcClock {
                     })
             });
 
-            esp_rom_delay_us(300u32);
+            ets_delay_us(300u32);
         };
     }
 
@@ -237,7 +242,7 @@ impl RtcClock {
                 })
             });
 
-            esp_rom_delay_us(3u32);
+            ets_delay_us(3u32);
         };
     }
 
@@ -343,7 +348,7 @@ impl RtcClock {
 
         // Wait for calibration to finish up to another us_time_estimate
         unsafe {
-            esp_rom_delay_us(us_time_estimate);
+            ets_delay_us(us_time_estimate);
         }
 
         #[cfg(esp32)]
@@ -364,7 +369,7 @@ impl RtcClock {
             if timeout_us > 0 {
                 timeout_us -= 1;
                 unsafe {
-                    esp_rom_delay_us(1);
+                    ets_delay_us(1);
                 }
             } else {
                 // Timed out waiting for calibration
@@ -670,7 +675,7 @@ impl WatchdogDisable for Swd {
 }
 
 pub fn get_reset_reason(cpu: Cpu) -> Option<SocResetReason> {
-    let reason = unsafe { crate::rom::rtc_get_reset_reason(cpu as u32) };
+    let reason = unsafe { rtc_get_reset_reason(cpu as u32) };
     let reason = SocResetReason::from_repr(reason as usize);
 
     reason
diff --git a/esp-hal-common/src/rtc_cntl/rtc/esp32c2.rs b/esp-hal-common/src/rtc_cntl/rtc/esp32c2.rs
index 262cbc07104..788c6a268fe 100644
--- a/esp-hal-common/src/rtc_cntl/rtc/esp32c2.rs
+++ b/esp-hal-common/src/rtc_cntl/rtc/esp32c2.rs
@@ -5,7 +5,7 @@ use crate::{
     clock::XtalClock,
     peripherals::{APB_CTRL, EXTMEM, RTC_CNTL, SPI0, SPI1, SYSTEM},
     regi2c_write_mask,
-    rom::regi2c_ctrl_write_reg_mask,
+    rom::rom_i2c_writeReg_Mask,
     rtc_cntl::{RtcCalSel, RtcClock, RtcFastClock, RtcSlowClock},
 };
 
diff --git a/esp-hal-common/src/rtc_cntl/rtc/esp32c3.rs b/esp-hal-common/src/rtc_cntl/rtc/esp32c3.rs
index fd3a6a666c9..243559e6f9b 100644
--- a/esp-hal-common/src/rtc_cntl/rtc/esp32c3.rs
+++ b/esp-hal-common/src/rtc_cntl/rtc/esp32c3.rs
@@ -5,7 +5,7 @@ use crate::{
     clock::XtalClock,
     peripherals::{APB_CTRL, EXTMEM, RTC_CNTL, SPI0, SPI1, SYSTEM},
     regi2c_write_mask,
-    rom::regi2c_ctrl_write_reg_mask,
+    rom::rom_i2c_writeReg_Mask,
     rtc_cntl::{RtcCalSel, RtcClock, RtcFastClock, RtcSlowClock},
 };
 
diff --git a/esp32-hal/build.rs b/esp32-hal/build.rs
index 94b3b98df14..0606210b850 100644
--- a/esp32-hal/build.rs
+++ b/esp32-hal/build.rs
@@ -18,6 +18,11 @@ fn main() {
         .write_all(include_bytes!("ld/hal-defaults.x"))
         .unwrap();
 
+    File::create(out.join("rom-functions.x"))
+        .unwrap()
+        .write_all(include_bytes!("ld/rom-functions.x"))
+        .unwrap();
+
     File::create(out.join("linkall.x"))
         .unwrap()
         .write_all(include_bytes!("ld/linkall.x"))
diff --git a/esp32-hal/ld/linkall.x b/esp32-hal/ld/linkall.x
index 49bd26aea2b..13d610bbc36 100644
--- a/esp32-hal/ld/linkall.x
+++ b/esp32-hal/ld/linkall.x
@@ -1,2 +1,3 @@
 INCLUDE "link-esp32.x"
 INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32-hal/ld/rom-functions.x b/esp32-hal/ld/rom-functions.x
new file mode 100644
index 00000000000..510ea2f24d9
--- /dev/null
+++ b/esp32-hal/ld/rom-functions.x
@@ -0,0 +1,5 @@
+PROVIDE(ets_delay_us = 0x40008534);
+PROVIDE(ets_update_cpu_frequency_rom = 0x40008550);
+PROVIDE(rom_i2c_writeReg = 0x400041a4);
+PROVIDE(rom_i2c_writeReg_Mask = 0x400041fc);
+PROVIDE(rtc_get_reset_reason = 0x400081d4);
diff --git a/esp32c2-hal/build.rs b/esp32c2-hal/build.rs
index 292510bcb3d..dea9774c18f 100644
--- a/esp32c2-hal/build.rs
+++ b/esp32c2-hal/build.rs
@@ -74,10 +74,16 @@ fn check_features() {
 
 fn add_defaults() {
     let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+
     File::create(out.join("hal-defaults.x"))
         .unwrap()
         .write_all(include_bytes!("ld/hal-defaults.x"))
         .unwrap();
 
+    File::create(out.join("rom-functions.x"))
+        .unwrap()
+        .write_all(include_bytes!("ld/rom-functions.x"))
+        .unwrap();
+
     println!("cargo:rustc-link-search={}", out.display());
 }
diff --git a/esp32c2-hal/ld/bl-linkall.x b/esp32c2-hal/ld/bl-linkall.x
index 9fbe9cd3584..e604dc6f8f8 100644
--- a/esp32c2-hal/ld/bl-linkall.x
+++ b/esp32c2-hal/ld/bl-linkall.x
@@ -1,3 +1,4 @@
 INCLUDE "memory.x"
 INCLUDE "bl-riscv-link.x"
 INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32c2-hal/ld/db-linkall.x b/esp32c2-hal/ld/db-linkall.x
index 7f3a441a201..c27dbb03de0 100644
--- a/esp32c2-hal/ld/db-linkall.x
+++ b/esp32c2-hal/ld/db-linkall.x
@@ -1,2 +1,3 @@
 INCLUDE "esp32c2-link.x"
 INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32c2-hal/ld/rom-functions.x b/esp32c2-hal/ld/rom-functions.x
new file mode 100644
index 00000000000..f52cacb2d0c
--- /dev/null
+++ b/esp32c2-hal/ld/rom-functions.x
@@ -0,0 +1,5 @@
+PROVIDE(ets_delay_us = 0x40000044);
+PROVIDE(ets_update_cpu_frequency_rom = 0x40008550);
+PROVIDE(rom_i2c_writeReg = 0x400022f4);
+PROVIDE(rom_i2c_writeReg_Mask = 0x400022fc);
+PROVIDE(rtc_get_reset_reason = 0x40000018);
diff --git a/esp32c3-hal/ld/bl-linkall.x b/esp32c3-hal/ld/bl-linkall.x
index 9fbe9cd3584..e604dc6f8f8 100644
--- a/esp32c3-hal/ld/bl-linkall.x
+++ b/esp32c3-hal/ld/bl-linkall.x
@@ -1,3 +1,4 @@
 INCLUDE "memory.x"
 INCLUDE "bl-riscv-link.x"
 INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32c3-hal/ld/db-linkall.x b/esp32c3-hal/ld/db-linkall.x
index 8eb0c0d6c07..02bc894cd57 100644
--- a/esp32c3-hal/ld/db-linkall.x
+++ b/esp32c3-hal/ld/db-linkall.x
@@ -1,2 +1,3 @@
 INCLUDE "esp32c3-link.x"
-INCLUDE "hal-defaults.x"
\ No newline at end of file
+INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32c3-hal/ld/rom-functions.x b/esp32c3-hal/ld/rom-functions.x
index 34431f0a21b..0c4c3555fb9 100644
--- a/esp32c3-hal/ld/rom-functions.x
+++ b/esp32c3-hal/ld/rom-functions.x
@@ -5,3 +5,8 @@ PROVIDE(cache_suspend_icache = 0x40000524);
 PROVIDE(cache_resume_icache = 0x40000528);
 PROVIDE(cache_ibus_mmu_set = 0x40000560);
 PROVIDE(cache_dbus_mmu_set = 0x40000564);
+PROVIDE(ets_delay_us = 0x40000050);
+PROVIDE(ets_update_cpu_frequency_rom = 0x40000588);
+PROVIDE(rom_i2c_writeReg = 0x4000195c);
+PROVIDE(rom_i2c_writeReg_Mask = 0x40001960);
+PROVIDE(rtc_get_reset_reason = 0x40000018);
diff --git a/esp32s2-hal/build.rs b/esp32s2-hal/build.rs
index 47417e9b1d7..866c8991fd5 100644
--- a/esp32s2-hal/build.rs
+++ b/esp32s2-hal/build.rs
@@ -18,6 +18,11 @@ fn main() {
         .write_all(include_bytes!("ld/hal-defaults.x"))
         .unwrap();
 
+    File::create(out.join("rom-functions.x"))
+        .unwrap()
+        .write_all(include_bytes!("ld/rom-functions.x"))
+        .unwrap();
+
     File::create(out.join("linkall.x"))
         .unwrap()
         .write_all(include_bytes!("ld/linkall.x"))
diff --git a/esp32s2-hal/ld/linkall.x b/esp32s2-hal/ld/linkall.x
index a63b704775a..d0f61614356 100644
--- a/esp32s2-hal/ld/linkall.x
+++ b/esp32s2-hal/ld/linkall.x
@@ -1,2 +1,3 @@
 INCLUDE "link-esp32s2.x"
 INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32s2-hal/ld/rom-functions.x b/esp32s2-hal/ld/rom-functions.x
new file mode 100644
index 00000000000..7c566b6a3c5
--- /dev/null
+++ b/esp32s2-hal/ld/rom-functions.x
@@ -0,0 +1,5 @@
+PROVIDE(ets_delay_us = 0x4000d888);
+PROVIDE(ets_update_cpu_frequency_rom = 0x4000d8a4);
+PROVIDE(rom_i2c_writeReg = 0x4000a9a8);
+PROVIDE(rom_i2c_writeReg_Mask = 0x4000aa00);
+PROVIDE(rtc_get_reset_reason = 0x4000ff58);
diff --git a/esp32s3-hal/build.rs b/esp32s3-hal/build.rs
index bcd4d725272..fc0d6b25704 100644
--- a/esp32s3-hal/build.rs
+++ b/esp32s3-hal/build.rs
@@ -14,11 +14,6 @@ fn main() {
         .write_all(include_bytes!("ld/rom.x"))
         .unwrap();
 
-    File::create(out.join("hal-defaults.x"))
-        .unwrap()
-        .write_all(include_bytes!("ld/hal-defaults.x"))
-        .unwrap();
-
     File::create(out.join("esp32s3.x"))
         .unwrap()
         .write_all(include_bytes!("ld/esp32s3.x"))
@@ -34,6 +29,8 @@ fn main() {
     // Only re-run the build script when memory.x is changed,
     // instead of when any part of the source code changes.
     println!("cargo:rerun-if-changed=ld/memory.x");
+
+    add_defaults();
 }
 
 #[cfg(feature = "direct-boot")]
@@ -50,11 +47,6 @@ fn main() {
         .write_all(include_bytes!("ld/rom.x"))
         .unwrap();
 
-    File::create(out.join("hal-defaults.x"))
-        .unwrap()
-        .write_all(include_bytes!("ld/hal-defaults.x"))
-        .unwrap();
-
     File::create(out.join("esp32s3.x"))
         .unwrap()
         .write_all(include_bytes!("ld/db-esp32s3.x"))
@@ -70,4 +62,22 @@ fn main() {
     // Only re-run the build script when memory.x is changed,
     // instead of when any part of the source code changes.
     println!("cargo:rerun-if-changed=ld/memory.x");
+
+    add_defaults();
+}
+
+fn add_defaults() {
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+
+    File::create(out.join("hal-defaults.x"))
+        .unwrap()
+        .write_all(include_bytes!("ld/hal-defaults.x"))
+        .unwrap();
+
+    File::create(out.join("rom-functions.x"))
+        .unwrap()
+        .write_all(include_bytes!("ld/rom-functions.x"))
+        .unwrap();
+
+    println!("cargo:rustc-link-search={}", out.display());
 }
diff --git a/esp32s3-hal/ld/linkall.x b/esp32s3-hal/ld/linkall.x
index 551a29d70ad..4497825665b 100644
--- a/esp32s3-hal/ld/linkall.x
+++ b/esp32s3-hal/ld/linkall.x
@@ -1,2 +1,3 @@
 INCLUDE "esp32s3.x"
 INCLUDE "hal-defaults.x"
+INCLUDE "rom-functions.x"
diff --git a/esp32s3-hal/ld/rom-functions.x b/esp32s3-hal/ld/rom-functions.x
new file mode 100644
index 00000000000..44328429bc6
--- /dev/null
+++ b/esp32s3-hal/ld/rom-functions.x
@@ -0,0 +1,5 @@
+PROVIDE(ets_delay_us = 0x40000600);
+PROVIDE(ets_update_cpu_frequency_rom = 0x40043164);
+PROVIDE(rom_i2c_writeReg = 0x40005d60);
+PROVIDE(rom_i2c_writeReg_Mask = 0x40005d6c);
+PROVIDE(rtc_get_reset_reason = 0x4000057c);